Integrated Roadside Vegetation Management Technical Manual

Integrated Roadside Vegetation Management Technical Manual thompsbb
A truck drives by a stretch of native vegetation in a roadside.

 

About This Manual

The objective of this publication is to provide basic technical support for new and existing Iowa county roadside programs. The manual is also intended to provide guidance to policymakers and engineers interested in adopting or expanding integrated vegetation management in county right-of-way.

Producing a manual that accurately describes the various aspects of integrated roadside vegetation management is best accomplished through a collaborative, integrated effort. Many of Iowa’s current roadside practitioners provided valuable assistance to the manual’s editorial team. Their expertise was instrumental to the creation of the manual and greatly appreciated.

Most of the photos in the manual were provided by the authors and roadside practitioners. Other image contributions are noted.

Funding for this manual was provided by the USDA-Natural Resources Conservation Service and the Iowa DOT’s Living Roadway Trust Fund.

Authors of earlier versions of this manual were Kirk Henderson, Jim Uthe, and Josh Brandt; much of their content remains in this version. 

The first three chapters (Introduction, Steps to Start a Roadside Vegetation Program, and Communications), have been reviewed and updated by a committee consisting of roadside managers (Tanner Bouchard, Wes Gibbs, Chris Henze, Megan Huck, Joe Kooiker, and Kolten Kudart), the LRTF coordinator (Tara Van Waus), IRM program manager (Kristine Nemec), and a private industry representative (Mike Heller) in 2024. The committee is continuing to review and update the remaining chapters in 2024. UNI graduate assistant Sean Thompson is entering and formatting the material on the website. Contact Kristine Nemec with any questions or suggestions regarding the manual: kristine.nemec@uni.edu or 319-273-2813.

Introduction

Introduction thompsbb
A vehicle travels on a road alongside colorful roadside vegetation.

 

What is IRVM?

Integrated Roadside Vegetation Management is an approach to right-of-way maintenance that combines an array of management techniques with sound ecological principles to establish and maintain safe, healthy, and functional roadsides. The IRVM toolbox includes judicious use of herbicides, spot mowing, prescribed burning, mechanical tree and brush removal, and the prevention and treatment of disturbances such as farm field runoff and herbicide overspray to existing vegetation. IRVM’s long-term objective is to reduce roadside maintenance by creating stands of durable, long-lived native plants.

History

History thompsbb

IRVM techniques were introduced to Iowa in the mid-1980s in response to the need for groundwater and surface water protection. Prior to that time roadside weed control had relied exclusively on herbicides, with most counties employing an application method known as blanket spraying, also known as broadcast spraying, to spray wide swaths of the roadside. 

Besides being expensive and potentially harmful, blanket spraying was an ineffective means of weed control, creating openings for weeds by stressing and weakening roadside grasses and eliminating beneficial broadleaf species. Iowa counties were spending a lot of money putting large amounts of herbicide into the environment and, at the same time, making little or no headway in the control of roadside weeds. Clearly, this type of roadside management proved unsustainable.

Another development of the mid-1980s was the Iowa Department of Transportation’s use of native prairie grasses and wildflowers to control erosion and save money on fuel since native plants require less mowing than cool-season grasses. A few county conservation boards were also experimenting with this naturally adapted, alternative vegetation for roadsides. 

When the Iowa Legislature officially adopted IRVM in 1988, the cornerstone of the program became the establishment and protection of native vegetation in Iowa roadsides. The Living Roadway Trust Fund was created the following year, supporting state, city, and county roadside projects. For more information about the history of IRVM and the LRTF, see the 2018 report created by Jean Eells entitled “Iowa’s Living Roadway Trust Fund and Integrated Roadside Vegetation Management Program.”

Since that time over 100,000 acres of state and county road right-of-way have been planted to native vegetation. Diverse stands of 15–45 prairie grass and wildflower species—all naturally adapted to local growing conditions—provide stable, low-maintenance roadsides for Iowa.

IRVM Program

IRVM Program thompsbb

Goals

  • Maintain a safe and effective road system.
  • Provide responsible and sustainable vegetation management.
  • Make the most of Iowa’s immense 847,000-acre roadside resource. 

Basic tenets 

  • Prevent soil erosion.
  • Control undesirable species in roadsides.
  • Do not rely exclusively on herbicides.
  • Plant the best-adapted vegetation.

The road to success for county roadside management

  • Create a full-time roadside manager position.
  • Hire a conservation-minded individual to run the program.
  • Give the roadside manager the power to succeed.

The integrated toolbox

  • Use the principle of species diversity for a strong, weed-resistant plant community. No single species is adapted to all roadside conditions. IRVM employs a mix of species suited to the range of growing conditions in a typical roadside and the varying climate conditions of an Iowa growing season. Any roadside planted to a monoculture will develop gaps for weeds to exploit.
  • Use herbicides sparingly. Overuse of herbicides weakens stands of grasses, allowing increased weed invasion. Careless use of herbicides also destroys beneficial broadleaf species that would otherwise help prevent weeds by occupying the same niche sought by broadleaf weeds.
  • Make more effective use of herbicides by spraying smarter with better training, better timing, and better technology.
  • Prevent disturbances. Farm field runoff and herbicide over-spray are common disturbances from adjacent land that destroy roadside vegetation and cause more weeds. Work with individual landowners to enlist their cooperation in reducing these negative impacts.
  • Conduct prescribed burns to promote healthy native vegetation. By burning native plantings every 3-5 years or so, trained and well-equipped crews use fire as the most effective means of managing fire-adapted prairie species.
  • Mow patches of weeds to reduce seed production and seed dispersal.
  • Use a variety of means to clear brush and trees before they block the vision of motorists, obscure signs, and become dangerous obstructions to errant vehicles.

The benefits of native vegetation

Iowa road departments plant native vegetation for a variety of reasons:

  • Native plants are durable, long-lived perennials well-adapted to Iowa’s climate and growing season.
  • A diverse native planting adapts to a wide range of soil and moisture conditions.
  • Native plants perform well in poor soils.
  • Extensive native plant root systems provide superior erosion control.
  • Deep roots and dense above-ground foliage reduce stormwater runoff by intercepting raindrops, slowing water flow, and increasing infiltration.
  • Extensive roots and decaying foliage further increase stormwater infiltration by adding organic matter to the soil, making it spongier and more absorbent.
  • Root systems penetrate six to eight feet or deeper, enabling prairie plants to survive drought and high salt concentrations.
  • Extensive root systems deprive weed roots of water, nutrients, and space.
  • Tall prairie vegetation shades out Canada thistle and other weed seedlings.
  • A wide swath of prairie grass in the right-of-way traps blowing snow in some situations, increasing the storage capacity of the ditch and reducing the amount of snow deposited on the road.
  • Native roadside plantings provide valuable food and cover for songbirds, game birds, and small mammals.
  • Native roadside plantings provide important habitat for agricultural crop pollinators.
  • Native plants add color and natural beauty to the right-of-way.
  • Tallgrass prairie roadside plantings restore a piece of Iowa’s natural heritage.

Progress to date

Herbicide use in Iowa roadsides has been reduced to spot-spray application and Iowa DOT and half of Iowa’s counties routinely plant native vegetation.

Since the early 1990s over 60,000 acres of state and 35,000 acres of county road right-of-way have been planted to native vegetation. Diverse stands of 20–45 prairie grass and wildflower species — all naturally adapted to local growing conditions — provide stable, low-maintenance roadsides for Iowa.

As of late 2023, 56 counties have an IRVM plan and 47 counties have a roadside vegetation manager. Counties with either a plan or a roadside vegetation manager collectively manage 308,000 acres of roadside vegetation using the principles of IRVM. 

As of late 2023, 19 cities have an IRVM plan. It is more difficult to estimate the number of city acres of right-of-way managed using IRVM techniques since unlike state and county highways, there is no comprehensive estimate of the amount of right-of-way in all Iowa cities.

The challenge

Encouraging the remaining counties and cities to place more of a priority on roadside vegetation is a challenge. Many are not so much against IRVM as they simply are not inclined to do much of anything with their roadside vegetation.

Of Iowa’s land area of 35,860,480 acres (56,273 square miles; 2020 Federal Land Ownership Report), 4.3% is public land. Roadside rights-of-way comprise around 60% of this public land within Iowa (Figure 1), representing a significant area where sustainable management techniques can improve water quality, reduce soil erosion, enhance aesthetics, and provide other public benefits.

A graph showing total acres of the various types of public land in Iowa.

Figure 1. Public land use in Iowa (acres). Sources: Tara Van Waus, Iowa Department of Transportation; Iowa Department of Natural Resources, 2023; Iowa County Conservation System, 2016, 2023; Vincent et al., 2020.

Steps to Start a Roadside Vegetation Program

Steps to Start a Roadside Vegetation Program thompsbb
Wildflowers in the foreground and power lines in the background.

Before developing a roadside program, it's important to assess the level of community interest and think about how the program might be structured within your county or city. Your program structure and potential goals can be inspired by conversations with officials and residents from your area and with those who already have implemented successful programs. Once a program is approved, there are resources for hiring and training staff, acquiring equipment, and implementing a program over the long term. This chapter discusses what to consider at the initial stages of a program. 

Evaluate Level of Interest in Starting a Program

Evaluate Level of Interest in Starting a Program thompsbb

Initial considerations 

Interest in starting a program that safely and strategically manages roadside vegetation using the principles of integrated roadside vegetation management may first arise from residents or county or city government employees.

People are most often interested in developing a roadside program because they want:

  • More organized and proactive roadside management.
  • More responsible and sustainable roadside vegetation management.
  • More cost-effective roadside management.
  • To manage roadsides for multiple purposes.
  • To take advantage of the Living Roadway Trust Fund to offset equipment and roadside inventory costs.

The full-time roadside manager

The best way to achieve common roadside program goals is to hire a full-time roadside manager. As the one overseeing all vegetation management activities, this person is focused and motivated to:

  • Perform weed and brush control activities in a timely, effective manner.
  • Save money by conducting more in-house operations.
  • Stay current with the latest products and technologies.
  • Establish and maintain healthy stands of native vegetation.
  • Install and maintain erosion control measures. 
  • Submit LRTF applications to bring in additional resources that address county needs.

As the county’s vegetation specialist, a roadside manager takes ownership of the county’s roadsides with pride and accountability. When one person coordinates every aspect of the program, the result is better roadsides. Although cities may not have the resources to hire a full-time roadside manager, in their IRVM plans they need to designate who will take leadership for how the roadsides are managed using the principles of IRVM.

A less expensive way to get started

A few counties have managed to plant a lot of roadsides to native vegetation without hiring a roadside manager.  These counties don’t get the same level of vegetation management but they do access the Living Roadway Trust Fund. The following are examples of how this has been accomplished:

  • The county looks for a vegetation-savvy individual already on staff in secondary roads — or elsewhere — and makes it part of the individual’s job to send in LRTF applications and do the planting.
  • The county engineer and conservation board director work together. The engineer applies for the seed — for ditch cleanouts and road projects — and conservation does the planting. 
  • The county finds a current employee (e.g., the engineer or somebody working under the engineer) who personally wants to see the county get active in IRVM. In addition to regular duties, this person applies to UNI for seed and works with road maintenance personnel to get it planted. 

Hopefully these efforts lead to the establishment of a full-time roadside manager position in a county. Planting native vegetation and maintaining healthy roadsides takes a sustained, focused effort. Even the board of supervisors cannot make this happen without having someone in a key position who wants the program to succeed.

Proposing a program to county or city decision makers

Those wanting to start a program, whether it is county or city employees or a citizen group, will need support from the decision makers who handle the local budget — the county board of supervisors, city council, or city manager — and from the head of the department that will supervise the roadside manager — the engineer, county conservation board director, board of supervisors, or city administrator. The decision makers will need to approve the IRVM plan and funding to hire a roadside manager. Program supporters will typically schedule a presentation about the need for a program at a public meeting of the supervisors or council.

When residents have worked to change their county or city’s roadside management practices, they organize prior to scheduling this presentation. Historically a citizens group has involved concerned residents who want less roadside spraying and more native vegetation. The effort can start with one person or a small group who recruits like-minded friends and associates. They meet informally, someone presides, someone takes minutes, and they lay out their goals over the course of a few meetings. 

The group can contact the TPC roadside program manager at any time during this process for questions or to acquire hard-copy resources for informing people about roadside programs. For example, the paper “Roadside Weeds, Brush, and Erosion: How Your County or City Can Manage Them to Create Safe, Healthy Roadsides and Roads” addresses a variety of benefits from having a program. Brochures to inform people about roadside programs and roadside vegetation topics are also available.

When the citizen group is ready, it should arrange a meeting with the board to present the outlined goals. Unless the supervisors are able to clear most of the agenda for one of their regular meetings, a special meeting will facilitate better discussion. Most of the citizen group members need to be present. The desired outcome at this time is for the board of supervisors to appoint a formal IRVM committee to look closely at the county’s current roadside management program and determine what’s best for the county. Recommended IRVM committee membership can include: a member of the board of supervisors, the county engineer, the road superintendent/foreman, the weed commissioner, a member of the conservation board, and key members of the original committee.

The best person or people for delivering the presentation about a proposed program depends on the local situation and who the decision makers trust. In some cases, it might be the county or city employee who would be responsible for developing the program and supervising the roadside manager. In other situations, decision makers might want to also hear from the roadside manager, engineer, or conservation board director from a nearby roadside program; Natural Resources Conservation Service (NRCS) employee; Soil and Water Conservation District (SWCD) commissioner; chair of the citizen group; someone representing farming interests; a weed control professional; LRTF coordinator; or the TPC roadside program manager. Some combination of the above may be effective. The point is to fortify the effort with respected individuals who can address the board of supervisors with candor and knowledge.

No matter who presents, having a high turnout of residents (ideally, including some with political influence) who support the program is important for showing broad local support. Residents can also write op-ed letters to the local newspaper and email or call their local officials to relay their support for a program.

Collect information on the current need for the program

County vegetation management survey

Supporters need to gather information demonstrating the need for the program. How much money and time are currently spent on managing roadside vegetation? Are county officials and residents satisfied with the level of erosion control, appearance of the roadsides, presence of noxious weeds, and safety issues such as the amount of brush near roads? If there is room for improvement, how might having an IRVM plan and a roadside manager provide the resources needed to more proactively and effectively manage the local roadside vegetation?

The County Vegetation Management Survey can serve as a basis for evaluating a county’s roadside vegetation management program. Obtaining meaningful responses may require interviews with members of the road maintenance crew or others directly involved. Consider county herbicide-use records, noting herbicide products, quantities, and costs. Consider spray records to determine who does the spraying, when it occurs, the technology used, and the miles covered each year.

Though responses to the survey questions can be subjective, they will help identify and prioritize personnel and equipment needs. The process will involve compromise. In the end, weed and brush control objectives are balanced against environmental concerns and limited county resources. With that in mind, determine an appropriate allocation of county resources. Also determine how much might be solved with better organization and efficiency.

A successful outcome to this process would be to have the board of supervisors dedicate a full-time position and budget for roadside vegetation management. The next step is to hire a resourceful person motivated to get the most done within that budget.

After a roadside manager is hired, the IRVM committee can become the IRVM steering committee, meeting with the new roadside manager on a regular basis; one suggestion is meeting monthly for the first year and quarterly thereafter. This committee sees that things are done as needed, supports the roadside manager’s efforts, and provides political support in times of need.

Where’s the savings?

Long-term savings are anticipated through the establishment of native plant species as better-adapted, more competitive vegetation. Immediate savings are realized by:

  • Having county personnel with LRTF-purchased equipment spray roadside weeds instead of hiring a contractor.
  • Having county personnel with equipment partially paid by the LRTF conduct tree and brush removal operations. 
  • Having county personnel install and maintain erosion control measures instead of hiring it done.

A professional vegetation specialist on staff can provide additional savings by:

  • Conducting stormwater inspections required under NPDES (National Pollution Discharge Elimination System).
  • Doing wetland delineations.
  • Preparing wetland monitoring reports for mitigations.
  • Developing a PROactive program of managing vegetation that dovetails with current road maintenance activities instead of a REactive one that is based on fixing problems after they have formed (The “savings” might be simply doing a much better job with the same amount of dollars).

Roadside manager insights

When considering the establishment of a new IRVM program, consider: money spent in weed control, money spent in contract seeding, money spent on erosion stone vs. best management practices. There’s lots of money to be saved with an IRVM program. Make it about money!

Depending on the size of a county’s projects and how much spraying, contract seeding, and maintenance is done, an IRVM program can save enough money to pay a roadside manager’s salary each year. On top of that, the county does not have to deal with contracts and has more control over how things are done.

-Wes Gibbs, Jones County, 2024


Potential objections to starting a program

Communicating the benefits to starting a program is important, but it’s also critical to be prepared to address the greatest challenges to starting and implementing a program. According to a 2016 survey of board of supervisors members and county conservation board directors, lack of support from elected officials or staff support, lack of staff capacity, other concerns in the county being a higher priority, the cost of starting a program, and lack of community support are among the greatest barriers to implementing IRVM practices (Stephenson et al. 2017). 

Survey respondents said challenges to using native species in particular include cost, adjacent landowners mowing the plantings, and acceptance internally or among contractors (Stephenson et al. 2017). A survey of engineers and roadside managers found similar barriers (Stephenson and Losch 2016). Both reports provide useful background information and generalized observations about how county officials make decisions regarding roadside management. Of course, being familiar with local decision makers’ values and perceptions of roadsides will allow citizen groups to be the most prepared for proposing a new initiative such as a roadside program.

A chart showing survey responses from conservation board members and county board of supervisors detailing the greatest barriers to implementing IRVM practices.A chart continuing to show survey responses from conservation board members and county board of supervisors detailing the greatest barriers to implementing IRVM practices.

Development of a Program

Development of a Program thompsbb

The simplest approach to developing a program is to think through all the program details with your staff, community members, and stakeholders. Here are some decisions that will need to be made.

Name of the program

Example roadside program names include Shelby County Roadside Management, Dallas County Integrated Roadside Vegetation Management Program, Linn County Right of Way Vegetation Management Program, and City of Center Point IRVM Program.

Goals and objectives

Goals are broad, long-term outcomes while objectives are shorter term, measurable actions to achieve goals.

Examples of roadside program goals from IRVM plans are listed below. Some programs further break these down into short-term goals (e.g., 0–5 years), medium-term goals (e.g., 5–10 years), and long-term goals (e.g., 10–20 years). 

  • Recognize and stop the spread of newly introduced invasive plant species countywide. These species need to be controlled before they become a major problem.
  • Minimize the need and use of herbicides and other chemical controls as methods for managing or eliminating undesirable plants. This includes incorporation of prescribed burning, spot-spraying, and strategic use of herbicides, pesticides, mowing, and tree removal.
  • Use a long-term integrated management program that promotes desirable, self-sustaining plant communities. Whenever practicable, native plant communities are incorporated with roadside vegetation plantings.
  • Enhance the scenic qualities of roadsides and their value as habitat for wildlife.
  • Provide a public relations program to build community support for the roadside management program.
  • Develop a neighborly policy for dealing with right-of-way encroachment issues.
  • Preserve and manage remnant prairie plant communities in the ROW through monitoring, prescribed fire, and brush removal.
  • Stabilize county road construction projects by seeding and providing adequate erosion control. Each site will be evaluated and cared for on an individual basis.

Examples of specific, measurable roadside program objectives (from the Dallas County IRVM plan) are listed below:

  • Spray at least 30 gallons of basal bark material annually. Encourage district operators to perform these treatments.
  • Monitor mowing operations conducted by secondary road personnel and make recommendations as requested. Encourage prescribed use of this technique to limit impact on plant and animal resources in right-of-way and keep Road Department in adherence with Iowa Code 314.17.
  • Mow all first-year plantings once during the growing season. Mowing will be conducted between late June and early August. Mow second-year and older plantings as necessity and manpower dictate.
  • Update website annually. Provide two press releases per year to local newspapers. Provide public service announcements and other opportunities for coverage as available.

To get ideas for other goals and objectives that would be appropriate for your county or city, look at approved IRVM plans that are online. All of the plans should include goals and some plans will also have objectives. 

Staffing and the percentage of time each staff members will dedicate to the program

Identify what staff member will implement the plan. County or city officials will sometimes have someone who is already on staff implement the plan, but counties will more often create a separate roadside vegetation manager position. 

Ideally the roadside manager who is hired will have wide-ranging knowledge and skills. The best candidates have a strong equipment background and good communications skills. Experience with natural resources, vegetation, or both is an important bonus. Candidates must like a challenge and be willing to learn as they go. It’s best to have the roadside manager on board before developing the county’s IRVM plan or conducting the roadside vegetation inventory. A generic position description can be personalized to fit your county’s situation. 

Roadside managers will be more efficient and able to get more done if they have the assistance of a permanent or temporary technician and summer help; most counties have at least 2,500 acres of roadside vegetation to manage. If budgets allow, a roadside program will employ:

  • A full-time vegetation specialist/roadside manager.
  • A full-time or 9-month roadside technician/assistant roadside manager.
  • Two seasonal employees.

Results from the latest roadside manager salary survey can help when budgeting for roadside manager, assistant, and summer help positions. Funding sources for roadside vegetation manager positions include the rural basic fund, secondary road fund, road clearing appropriation, and county conservation board.


Roadside manager insights

Creating a new position for a roadside manager might be difficult. So a realistic inventory of existing personnel may help. Who has a green thumb? Who has the political savvy to survive? After appointing a roadside manager, an inventory of equipment and facilities is next. It’s way easier to start a program if existing tractors, trucks, etc. can be used at first. When times get better, the program can grow. At the end of the day the program survives on the relationships with the county engineer, BOS, etc.

-Joe Kooiker, Story County, 2024


Advisory committee: community partners who can help you with referrals, advertising, and implementation

An IRVM steering committee, also known as an advisory committee, meets regularly to provide guidance to the roadside program and be kept informed about the roadside program’s activities and challenges. They are also helpful for communicating about the benefits of having a program within the community and providing political support as needed. 

Steering committees may be formed at any time but most often arise from a committee formed during the initial effort to establish a program or shortly before or after a roadside manager is hired. Committees typically meet between two and four times a year and consist of between five and ten members representing the private and public sector. The committee may consist of the following members:

  • A member of the board of supervisors (highly recommend at least one).
  • County engineer.
  • Road superintendent/foreman.
  • Weed commissioner if this is a separate position from the roadside manager.
  • A member of the conservation board.
  • Key members of the original committee formed to establish a roadside program
  • Educator.
  • Soil and Water County Conservation District representative.

The county engineer, conservation board director, or initial IRVM committee members may recommend people to appoint but the board of supervisors has the ultimate authority for appointing members, who often serve three-year staggered terms. An example initial setup for appointments is below. Once all of the 1-year-term people serve, then three people are elected for 3-year terms and once all of the 2-year term people serve, then three people are elected for 3-year terms.

3 persons — 1-year term

3 persons — 2-year term

4 persons — 3-year term

Committees elect a chairperson and secretary and meetings are subject to Chapters 21 and 22 of the Iowa Code concerning open meetings and public records. 

Program organization/location

When deciding where to locate a county roadside program and who should supervise the roadside manager, keep in mind that greater independence allows for better planning and timely operations. Sometimes reorganizing within a department or restructuring of departments is necessary to give roadside management personnel the autonomy to meet objectives. County programs operate successfully within the engineer’s office, the county conservation board, or as an independent department. All three have advantages.

A diagram showing organizational options for structuring a county roadside program.

 

Generating support for the program

The "Communication" section has many ideas for developing and maintaining both internal and public support for a program. Members of a steering or advisory committee can generate goodwill toward the program by communicating within their networks; regular communication with the committee is important so they know about the roadside managers’ projects and what type of information to relay.

Working on projects that visibly show progress in a relatively short amount of time, such as brush control or seedings with signage, can help garner support for a new program. The appropriate level and type of publicity for a new program can vary depending on the county or city’s goals and progress on specific projects.


Roadside manager insights

I wouldn’t over-publicize a new program. It can bring too much scrutiny and pressure. Hire or appoint a roadside manager and do some visible projects (seedings, erosion control, tree removal, etc.). Then promote the program through finished works.

-Jeff Chase, Des Moines County, 2010


Evaluating the success of the program

Completing an IRVM plan and a county vegetation survey can identify goals and objectives that serve as the basis for evaluating the program. Examples of ways counties have evaluated aspects of program success include:

  • Comparing results of county-wide roadside vegetation inventories.
  • Creating project reports documenting plant establishment on an annual basis for larger (more than one acre) plantings on hard-surfaced roads.
  • Evaluating effectiveness of herbicides and other weed control measures in managing problem areas with a lot of invasive species.
  • The IRVM advisory committee discussing the program progress on an annual basis at one of its regular meetings.

Budget

These items may need to be included when anticipating the cost of a program:

  • Salary full-time roadside manager.
  • Salary full-time technician.
  • Salary temporary assistants.
  • Overtime full-time roadside manager.
  • Overtime full-time technician.
  • Overtime temporary assistants.
  • Contract labor.
  • FICA — county or city contribution.
  • IPERS — county or city contribution.
  • Health insurance.
  • Life insurance.
  • Dental insurance.
  • Long-term disability.
  • Chemicals and gases — herbicides.
  • Stationary and forms.
  • Minor equipment and hand tools.
  • Education and training.
  • Operations and construction equipment.
  • Fertilizer and seed.

Implementation

Implementation thompsbb

Once a county or city has decided to move forward with implementing a program, the following steps will need to be taken.

Memoranda of understanding 

Get any necessary memoranda of understanding or agreements signed by your partner organizations.

IRVM plan

Counties and cities that want to apply for LRTF grants and request free native seed will need to develop an IRVM plan that is signed by the appropriate county or city officials. The plan must contain the information contained in the IRVM Plan Outline for Counties, State Agencies and Cities over 10,000 in Population form or the IRVM Plan for Cities Under 10,000 Population form. These forms and approved plans are on the LRTF website

The LRTF coordinator is available for any questions that arise as you work on your plan; email the final plan to the LRTF coordinator for approval. Both IRVM plans and LRTF grants must be submitted by June 1 if a county or city is applying for LRTF grants at the same time. An approved plan should be updated and submitted for review by the LRTF coordinator every five years.

IRVM plans developed prior to 2015, when the LRTF implemented the latest plan requirements, are considered inactive. Counties or cities who do not have plans that meet the latest requirements are ineligible to apply for LRTF grants or request native seed.

County/city resolution passed

The county board of supervisors or city will need to pass a resolution establishing the program. Resolutions may also be passed regarding sections of Iowa code that pertain to IRVM programs, such as 314.22, and to accept LRTF grants.

Pass budget

Some counties or cities pass the budget for the roadside program separate from other expenses while others absorb the budget into a department’s budget. In either case it will need to be approved by the relevant county decision makers.

Hire and train staff

After you have identified who will be your county or city’s point of contact for implementing your IRVM program, provide the TPC roadside program manager with the person’s mailing address, email address, and phone number. The TPC roadside program manager will then send the roadside manager the following information:

  • A request for a 3–5 sentence bio and photo for social media and the Roader’s Digest e-newsletter.
  • The new roadside manager’s address and phone number (if that wasn’t provided already).
  • Information on how to reach out to nearby roadside managers who are on a list of roadside managers who have expressed willingness to be job shadowed by a new roadside manager.

The TPC roadside program manager will then connect the person to the Iowa Roadside Management network by:

  • Updating the TPC website with contact information and updating the internal email mailing list consisting only of roadside manager email addresses.
  • Adding the new roadside manager to the roadside management Google Group/email list and Roader’s Digest list, which each consist of anyone interested in roadside vegetation management.

Annual operations

Many programs find it helpful to create a list of annual operations so the roadside manager can understand what their responsibilities will be like throughout the year. Here is an example of a list of annual operations that appears in IRVM plans. Some programs have a more detailed list that is organized by month.

January–March: Cut trees and brush, update seeding areas, Association for Integrated Roadside Management winter meeting, Weed Commissioner Annual Conference, annual weed report to Supervisors and State Commissioner, meet with board of supervisors on roadside budget, equipment maintenance 

March–April: Prescribed burning, LRTF Grants, inventory, spring seeding as weather allows, hire/train seasonal employees

April–October: Seeding, weed commissioner duties, spraying road ditches, spraying brush, mowing 1st and 2nd year seeded areas, manage seasonal employees, annual roadside conference

October–December: Cut trees and brush, fall seeding, equipment maintenance, reports, material inventory, roadside budget

Training

Training thompsbb

Job shadowing neighboring roadside manager

After the roadside manager has started, the TPC roadside program manager will give the person an opportunity to job shadow an experienced roadside manager from a nearby county who is willing to be a resource for new roadside managers. This allows the new roadside manager to develop an early one-on-one relationship with a peer and learn how another county approaches roadside management.

Chemical safety/handling

Controlled pesticide application is another useful part of the IRVM toolkit. Pesticide use
on roadside ROWs is considered public pesticide application, which requires a Commercial Pesticide Application license. To become certified, the roadside manager must pass a 50-question, closed book exam over the Core Manual - Iowa Commercial Pesticide Applicator Manual; pass a 35-question exam specific to right-of-way pesticide application; and pay a $15 fee for public applicators. Information on testing dates can be found on the "Applicator Licensing and Certification" page of the Iowa Department of Agriculture and Land Stewardship website. 

Commercial driver’s license – Iowa DOT

To obtain a commercial driver’s license (CDL), applicants must complete applicable entry-level driver training from a registered training provider. Training providers can charge an average of $4,000. For more information, see the Training Provider Registry on the Federal Motor Carrier Safety Administration website.

Chainsaw safety

There are several options for in-person chainsaw safety training:

  • Have a representative from the company that manufactures the chainsaws you are using come to your shop and train your employees. One advantage of this is that they can also look at your equipment and let you know if the equipment needs maintenance. A drawback is that some representatives may be less familiar with providing field demonstrations of safe brush removal techniques.
  • Find experienced county conservation employees who periodically conduct chainsaw training.
  • Find a nearby land management organization or nature center that periodically conducts chainsaw training.
  • Attend chainsaw training at a community college with a land management program. For example, Hawkeye Community College has offered chainsaw training that it is classroom-based with a representative from Stihl.
  • Get trained from an organization that regularly conduct chainsaw training; these are more common in Wisconsin and Minnesota. One example is Blue Heron Stewardship in Wisconsin.

These are some useful online resources for chainsaw training:


Roadside manager insights

Stihl posts very good chainsaw safety, operation, & maintenance videos on YouTube. I’ve had good success having one of my more experienced and willing crew members present the video and give pointers to illustrate how the video applies to our particular situation. I think that formula works just as well as an outside trainer in making a connection to the crew. 

-Steve Struble, Harrison County Engineer, 2020 


Prescribed burning

Controlled burns are a useful and cost-effective IRVM management tool. Burning roadsides helps to control weeds, eliminate brush, and return nutrients to the soil. The Iowa DNR Forestry website lists relevant courses in prescribed burning. To become Red Card certified in controlled burns, one must complete a one-day field day (as part of the S-130 Firefighter Training course), as well as a series of online courses. Field day options are usually listed on the Iowa DNR website in early spring.

Plant identification

Identifying native and non-native plants is a vital skill for a roadside manager. While recognizing noxious weeds may seem like the most important part of a weed commissioner’s work, it is just as important to recognize where native prairie plants remain. Many prairie remnants are found on the sides of roads and train tracks, as both are traditionally undisturbed areas. Remnant prairies are especially well-adapted for their environment, which makes them valuable sources for native seed. 

Plant identification resources exist for every learning style. Commonly used resources are listed below. 

Webinars

Webinars produced by the Tallgrass Prairie Center

Other webinars

  • Golden Hills Resource Conservation and Development (RC&D): Plant identification webinar recordings, many that are taught by botanist Dr. Tom Rosburg. Some of the webinars might be especially useful to roadside managers.
    • Invasive and Native Look-alike Plant Species in Iowa
    • Common Weeds & Invasive Species of Iowa
    • Cirsium (Thistle Identification)

Books

  • Newcomb’s Wildflower Guide (Newcomb, 1989): Newcomb’s is the textbook used for the Botany Beginners courses. This guide contains both native and non-native wildflowers, shrubs, and vines. Its breadth (1,375 species) and easy-to-use key make it a valuable resource.

  • Wildflowers of the Tallgrass Prairie (Runkel and Roosa, 2010). This guide contains high-quality images of 78 species, most of which are wildflowers. This guide is particularly useful for prairie remnants and information on ethnobotany. It is arranged in order of flowering time. This guide doesn’t include a key and has less species than the other books mentioned. The guide’s creators also produced complementary field guides for the wetlands and forests of the upper Midwest. 

  • Prairie Plants of the University of the Wisconsin–Madison Arboretum (Cochrane, Elliot, and Lipke, 2015). The most detailed guide on this list. Prairie Plants includes horsetails, ferns, rushes, sedges, grasses, shrubs, vines, weeds, and wildflowers, and features both flower and fruit photos. Because Prairie Plants is arranged by plant family, and doesn’t have a key, it is recommended for audiences who are already familiar with botany.

  • Weeds of the Great Plains (Stubbendieck, 2003). Common weeds found in Nebraska and neighboring states, including Iowa.

  • The Tallgrass Prairie Center has also produced a native seed production manual, a seed-bearing plant identification guide, and a guide to tallgrass prairie seed and seedling identification. 

Websites

  • USDA PLANTS Database: Located within the USDA website. PLANTS provides standardized information about vascular and nonvascular plants, and is useful for finding federal and state listings of weeds that are considered introduced, invasive, and noxious. 

  • Minnesota Wildflowers: Field-guide style website with photos and information on Minnesota wild plants, with a variety of methods to search for plants. 

  • Illinois Wildflowers: Provides useful ecological information on the wild plants of Illinois. 

  • Iowa Weed Commissioners: Includes weed identification brochures from nearby states and the Hawkeye Cooperative Weed Management website.

Plant ID Apps

Because plant ID apps aren’t 100% accurate, it is important to learn the basics of plant identification using the resources above and be able to understand plant identification techniques from a professional perspective. That said, it is useful to be aware of the more reputable plant ID apps as a tool in your toolbox and to be aware of for members of the public who ask about apps. Here are two that have been well-reviewed for amateur botanists.

Conferences and field days

Conferences attended by roadside managers

The conferences listed below offer opportunities to network and continue relevant training. Most roadside managers attend the winter AFIRM meeting and the annual roadside conference. Those who are also weed commissioners attend the weed commissioners conference, also known as the Iowa invasive species conference. All three conferences include a lot of information directly related to roadside vegetation management and counties and cities would do well to budget for roadside managers to attend these meetings. 

The other meetings listed are attended by a smaller number of roadside managers, often those who live near the meeting location. The TPC roadside program manager may have a limited number of scholarships available to cover the registration fee for roadside managers who want to attend these meetings. The registration fee for roadside managers who table to promote roadside management at the Streets and Roads Conference, Engineers Conference, and Statewide Supervisors Meeting may also be covered.

Winterfest—Iowa County Conservation System

  • Typically held for three days the third or fourth week of January in Coralville.
  • Provides a variety of sessions led by academics and professionals working in conservation in Iowa and in nearby states.
  • Attended by variety of county conservation staff, with many college students attending on Wednesday for collegiate day; vendors with tables.

Winter Meeting—Association for Integrated Roadside Management (AFIRM)

  • Annual one-day meeting in late February or early to mid-March.
  • Topics of interest to roadside vegetation managers are discussed.

Invasive Species Conference—Iowa Weed Commissioners’ Association

  • Annual three-day meeting in late February or early to mid-March over the days immediately following AFIRM meeting; a special meeting for new weed commissioners is held during the late afternoon the day of the AFIRM meeting.
  • Opportunity for continuing education in pesticide application.
  • Attended by weed commissioners and conservation professionals whose role includes weed management; presentations by researchers and practitioners; vendors with tables.

Iowa Prairie Conference

  • Held every other year (typically in the years the North American Prairie Conference isn’t held) at a location in Iowa.
  • Talks about managing and restoring tallgrass prairie, with a focus on Iowa.
  • Attended by natural resource professionals, researchers, and prairie enthusiasts.

North American Prairie Conference

  • Four-day meeting held every other year during the summer at a location in the central U.S.
  • Conference focused on developments in managing and restoring tallgrass prairie ecosystems.
  • Attended by researchers, students, and stewardship professionals; vendors with tables.

Roadside Conference—Iowa Roadside Management

  • Annual three-day meeting in September or October, including an afternoon of field trips.
  • Attended by roadside managers, DOT staff, and others interested in roadside management; vendors with tables.

Upper Midwest Invasive Species Conference

  • Three-day meeting held every other year in mid-October to mid-November.
  • One of the most comprehensive and largest invasive species conferences in the U.S.
  • Attended by wide variety of researchers, natural resource professionals, and government agency staff; vendors with tables.

Conferences with a roadside management table

The TPC Roadside Office typically has a table about roadside vegetation management at some of the events below; either the TPC roadside program manager or roadside managers may table. A small number of roadside managers may also attend some of these conferences on behalf of their county or city without tabling.

Statewide Supervisors Meeting

  • One-day meeting held in early February in Des Moines.
  • Attended by members of county boards of supervisors; vendors with tables.

Iowa State Association of Counties Spring Conference

  • Three-day conference held in March in Des Moines.
  • Attended by all types of county employees; vendors with tables.

Iowa Statewide Association of Counties Fall Conference

  • Three-day conference held in August in Des Moines. 
  • Attended by all types of county employees; vendors with tables.

Iowa County Conservation System Fall Conference

  • Three-day conference held in mid-September at a location in Iowa.
  • Attended by county conservation staff, with more conservation board directors and others in leadership positions attending than at Winterfest; vendors with tables.

Iowa Streets and Roads Workshop and Conference

  • One-day workshop and two-day conference held in late September in Ames.
  • Attended by secondary road and street maintenance supervisors and staff and others interested in road and street maintenance; vendors with tables.

County Engineers Conference

  • Three-day conference held in mid-December in Des Moines.
  • Attended by county engineers and other secondary road department staff; many vendors with tables.

Field days

Many conservation-oriented organizations and equipment dealers offer useful field days. The organizations listed below host a variety of virtual and in-person field events.

Practical Farmers of Iowa

  • Series of free field days over the growing season on a wealth of topics related to sustainable agriculture, including relevant topics like prairie seeding and burning.
  • Attended by natural resource professionals and private landowners.

Prairie on Farms Program (Tallgrass Prairie Center)

  • One or two field days on planting successful native plantings on agricultural fields; held during some years, not necessarily every year.
  • Attended by farmers and natural resource professionals interested in prairie restoration.

Hawkeye Cooperative Weed Management Area invasive species field day 

  • Annual field day held in August at a location in eastern Iowa.
  • Topics include managing various kinds of invasive species and other land management topics.
  • Attended by natural resource professionals and private landowners; some vendors with tables.

Iowa Learning Farms 

  • Free online webinar series on topics related to land management, from soil health to improved water quality to pollinator conservation. 
  • All webinars are archived on the Iowa Learning Farms website.

Email Lists and E-Newsletters

Joining an email list and e-newsletter can be a good way to keep up with the latest news in roadside equipment and vegetation management. Here are some that roadside managers have found useful.

Roadside management email list

The TPC roadside program manager maintains a Google Group email list called Roadside Management. Email the TPC roadside program manager to be added to the list. Anyone who is part of the group can search archives of previous questions and pose a question to the list at roadside-management@uni.edu. Some people prefer to ask the TPC roadside program manager to post their question the list. Members pose questions about others’ experience with equipment, share job ads, and post time-dependent news that can’t wait for the monthly Roader’s Digest e-newsletter.

Roader’s Digest e-newsletter

The Roader’s Digest e-newsletter, the “Newsletter of the Iowa Integrated Roadside Vegetation Management Program,” was begun by the TPC roadside program and existed as a paper newsletter from 1989 to 2001. In 2017 it was reinstated as a monthly e-newsletter.

Midwest Invasive Plant Network e-newsletter

The MIPN e-newsletter relays information on invasive plant news in the region. People can sign up on the MIPN website and search past newsletters on the MIPN website.

Iowa Native Plants

The Iowa Native Plant Society maintains a discussion list available to anyone interested in native plants.

Professional Organizations

Belonging to one or more of the following organizations can be helpful for making professional connections and keeping up with innovations in vegetation management: 

Purchase Any Program Supplies and Equipment

Purchase Any Program Supplies and Equipment thompsbb

Taking advantage of the Living Roadway Trust Fund

Since 1990, counties have enjoyed support from the Iowa Department of Transportation’s Living Roadway Trust Fund. Roadside managers submit applications each year to acquire resources for their program. The LRTF does not fund salaries, trucks, or tractors. Beyond that, it’s up to the county to be resourceful. While eligibility for this funding requires only that a county have an IRVM plan on file with the LRTF, a county’s commitment to IRVM is a factor when grant applications are reviewed. A full-time roadside manager on staff demonstrates strong commitment. Applications are due each year on June 1.

Typical equipment needed for a program

See the latest LRTF Funding Guidelines or contact the LRTF coordinator to verify if LRTF funds can be used for a piece of equipment. LRTF grants can be used toward most of these items:

  • Pickup truck, pretty heavy duty (3/4-ton, large enough for fire pumper unit).
  • Tractor, 60 hp with dual rear axle.
  • Flatbed truck for herbicide spray rig.
    • Many counties are going with flatbed truck mounted spray units with chemical injection, spray heads and GPS. The Living Roadway Trust Fund will help with purchase up to 80%. 
    • Sprayers are not the highest priority for LRTF so the bigger the cash match the county comes up with, the better your chances. You can spend $25,000 pretty easily. 
  • Truck or trailer for hydroseeder.
  • Broadcast seeder.
  • Hydro-Seeder (800 gal. minimum with mechanical agitation).
  • Native seed drill (6-foot).
  • Cultipacker.
  • Boom mower.
  • Chainsaws.
  • Brush chipper.

There are many other pieces of equipment counties use. Many can be funded 80% through LRTF. This includes seed storage room, herbicide storage, and equipment shed: 

  • GPS. 
  • UTV.
  • Fire rigs and safety equipment.
  • Culti-packer. 
  • Straw mulch blowers. 
  • Harrows and drags.
  • Trailers.             
  • Silt fence equipment. 
  • Chainsaws.
  • Equipment shed. 
  • Brush mowers. 
  • Broadcast seeder.

Roadside vegetation inventories  

The most effective roadside management starts with accurate information about roadside conditions. Inventory information helps set management priorities and provides baseline data for measuring program success.

Information collected in a roadside inventory includes herbaceous cover, tree and brush cover, weed concerns, bare areas, and areas with erosion and encroachment. The inventory process typically involves a windshield survey of roadside conditions throughout the county, recorded every quarter mile, or as needed. The individual (or individuals) conducting the inventory must be able to identify weeds, distinguish native prairie vegetation from non-native grasses, and recognize areas of erosion and encroachment. If more than one individual is conducting the inventory, a leader must provide training to ensure accurate, uniform data collection.

LRTF funds can be used to hire someone to do the inventory. The roadside manager and county engineer are included in planning and training so the collected data will be of maximum use to the county. Six to eight weeks are allowed for the process, ideally in late summer and fall since this is the easiest time to identify stands of native vegetation.

Inventories funded by the LRTF must be recorded on GPS devices. Software for collecting and recording roadside inventory information has been developed and is available free of charge from the LRTF. The LRTF also funds the purchase of GPS units, mapping software and laptop computers.

People who may be hired to conduct a roadside vegetation inventory include:

  • Faculty and students from a nearby college who are familiar with conducting plant surveys.
  • Leland Searles, Consultant and Photographer, Leeward Solutionssearleslr@msn.com, 515-979-6457.

Identify prairie remnants

Every county in the state has a few roadsides containing small patches of native plants descended from the original prairie. Prairie remnants, as they are called, may possess just a few species of note or they may be quite diverse. Either way they provide a glimpse of the past and are valued as sources of genetic material and models for future prairie restoration. They all merit protection.

Look for prairie remnants where an old railroad right-of-way parallels the highway or where land may have been too rocky or too wet to till. A thorough survey of roadsides in your jurisdiction is the best way to document the location of remnants and prevent their destruction in the future. Generally, do not try to enhance a remnant by inter-seeding with native seed unless that seed comes from remnants in the immediate vicinity.   

Native seed (this is separate from LRTF grants)

Since 1998 nearly all the native seed planted in county right-of-way has been paid for with Federal Highway Administration (FHWA) funds secured by the TPC roadside program. The FHWA program that is the source of this grant has undergone several name changes over the years and is currently calls the Transportation Alternatives Set-Aside Program. These funds are approved year to year, and seed is distributed to participating counties and cities at no cost to them.

Counties must have an approved IRVM plan on file with the LRTF to request the seed and provide the labor and equipment to plant it. These native seed mixes typically have a value of $250–$350/acre and can only be used within road right-of-way. According to the grant requirements, the seed cannot be used along trails that are outside of the road right-of-way, for example.

In September of October of each year the TPC roadside program manager emails programs that are eligible to request seed and asks them how many acres worth of seed they would like to receive the following year. Roadside managers will need to provide maps of locations where seed will be drilled or planted using heavy equipment that may cause rutting of the soil greater than six inches. The TPC roadside program manager will submit this information to the DOT archaeologist for review to ensure no Indigenous burial sites will be impacted. Maps do not need to be provided for sites that will be hydroseeded or broadcast seeded since these seeding methods cause shallow soil disturbance that will not affect burial mounds.

The seed is typically distributed over a 2-day period in April, May, or June, at the shed south of the Tallgrass Prairie Center and all of the seed received must be planted by December 31 of the following year. The FHWA requires that every six months the TPC roadside program manager ask seed recipients to turn in a seed report form and maps showing where the seed was planted.

A few counties have created their own seed production plots to supplement the seed they obtain from the TPC roadside program. Counties may occasionally purchase seed from commercial sources beyond what they receive from the TPC.

Create any data collection tools and processes needed to evaluate the program

GIS mapping tools can be used to record data on roadside management activities such as brush cutting, spraying, and invasive species removal.

Communication

Communication thompsbb
A microphone is poised in front of an empty auditorium.

Effective communication with county or city officials and the public is essential for building and maintaining support for a program and preventing problems caused by miscommunication. Although roadside managers are busy and handle many responsibilities as part of their job, regularly investing time in communication can pay dividends in helping a program succeed.

Some roadside managers have been surprised at how they have been able to successfully convert individuals such as truck drivers, engineers, and board of supervisors members who were initially disinterested in prairies into supporters of their roadside programs. Good communication can be effective in garnering support.

No matter who you are interacting with, best practices include:

  • Being available and approachable to anyone seeking information or assistance.
  • Fostering trust by actively listening to understand and consistently following through to accommodate stakeholders’ needs;
  • Promptly addressing complaints, concerns, and questions.
  • Understanding the products and techniques used and effectively explaining them to individuals unfamiliar with natural resource work.

Specific strategies for communicating well with different stakeholders are presented below. The amount of publicity used to promote a roadside program can vary by county or city. A low-key approach might yield better results depending on local dynamics. 

County Officials

County Officials thompsbb

County board of supervisors

Board of supervisors members can better understand roadside management programs if the roadside manager provides quarterly reports and invites them on regular shop visits and tours. Engaging board of supervisors members in discussions aligned with their interests, such as spraying weeds and brush mulching, helps build a good relationship with the BOS.

For example, aggressively spraying noxious weeds during the peak months of June and July is one way to gain positive attention from board of supervisors officials. Demonstrating progress in problem areas through spraying and quantifying the work accomplished through acres treated shows the value of the roadside manager role. Showcasing individual projects and demonstrating equivalent effort in work compared to roads employees also helps garner support.

County roads department

Keeping engineers and secondary roads superintendents updated about planned actions contributes to coordination and alignment with road projects. Involving secondary roads employees in brush control activities that transition from manual to more effective methods establishes positive rapport with the roads department.

Offering training sessions on invasive plants, herbicide safety, and environmental concerns to secondary roads employees is beneficial.

Emphasizing the importance of maintaining good relationships and effective communication with coworkers, engineers, and road superintendents eases workflows and decision-making processes.

County conservation

Leveraging collaboration between departments, such as the Conservation Board and Public Works staff supports the transition toward an integrated approach in proposing ideas.

Reports about Iowa county official perspectives on roadside vegetation management

In 2016 and 2017 the TPC roadside program manager conducted LRTF-funded research with social scientists from the UNI Center for Behavioral Research on how county roadside managers, county engineers, county conservation board directors, and chairs of the boards of supervisors perceive roadside vegetation management. All Iowa county officials, regardless of if they had a roadside program or not, were surveyed.

Survey questions for roadside managers and engineers primarily focused on how respondents manage roadside vegetation. Example questions included the following:

  • What have been your primary challenges in the greater use of native species?
  • How often are your plantings typically mowed within one year of seeding? 
  • What weed prevention measures does your agency currently undertake in your county?

Survey questions for chairs of the board of supervisors and county conservation board directors included the following:

  • What factored into your county’s decision to hire a roadside manager?
  • How concerned are you about the possible effects of local prescribed burns?
  • How much impact do each of the following items have on your county’s decisions about roadside vegetation management?

Reports summarizing results from all of these surveys can be found on this webpage.

Landowners

Landowners thompsbb

Understanding and responding to landowner concerns

If landowners are dissatisfied with how roadside vegetation appears or is being managed, it is important to ask clarifying questions to understand their concerns before responding. Two common landowner concerns with potential clarifying questions and responses are provided below as examples. The questions and responses were gathered from audience feedback during a talk about communication at the 2023 roadside conference.

Example 1. A landowner is unsatisfied with the appearance of roadside plants and brush. Some potential clarifying questions are below: 

  • What brought you to the country from the city?
  • Define unclean look? What specifically is unappealing to you about the roadside?
  • What do you find undesirable?
  • What would you like to know about how the roadsides are managed?

There are some example personalized responses that are tailored to the landowner’s concerns:

  • Talk about the vegetation, introduce species and help aid a connection for them with specific plants, which may change the person’s mind about the whole look.
  • Enhancing roadsides is an investment for Iowa’s native habitat and wildlife that also keeps our roadsides safe.

Example 2. A landowner is concerned about roadside weeds encroaching onto their property. Some potential clarifying questions are below:

  • Which weeds are causing you problems?
  • What specific weed pressure issues do you have?
  • What practices are you using to control weed pressure on your property? 

There are some example personalized responses that are tailored to the landowner’s concerns:

  • Let’s work together to determine where the problem is coming from and a future management goal.
  • I would like to come take a look at the problem, assess the area, and come up with a solution for both the county and you as a landowner.
  • Native long-lived plants in roadsides suppress the kinds of weeds that tend to cause problems in crop fields.
  • The weeds are coming from the neighbor, not us.

Preventing mowing and spraying of plantings

Some roadside managers have found that talking to directly to landowners or placing doorknob hangars that include contact information on people’s houses explaining why you are planting and maintaining native plants in the roadside helps prevent adjacent landowners from mowing or spraying roadside vegetation. Communication is key. Sometimes, after you have spent years maintaining a planting or remnant, you may still find that the adjacent landowner routinely mows it or intentionally sprays it with herbicides, violating the Iowa Code (check the most updated versions of Iowa Code 317.11 and 317.13, which include restrictions on landowners regarding haying, burning, mowing, or spraying in areas managed using an IRVM plan). What can you do? 

If you want to pursue monetary damages you can consult with your county attorney who can notify the landowner responsible for the damages. If the landowner or farm operator has inadvertently sprayed the planting, they may have liability insurance that will pay for damages and can reach a settlement with the county attorney, usually without legal action. The settlement time is generally around 9-12 months. Word gets around and it sends a message to other people that the county will enforce Iowa Code that applies to roadside vegetation. 

For sites that have been sprayed you can call the Pesticide Bureau at the Iowa Department of Agriculture and Land Stewardship (IDALS) to send out a pesticide inspector who will take vegetative samples to determine if spraying/drift occurred, conduct an investigation, and issue a report, but IDALS cannot enforce anything on your behalf; that is up to the county. 

The Iowa State Association of Counties General Counsel (515-369-7014) can be a good resource for questions regarding sections of Iowa Code that apply to roadside vegetation management.

Letters and permits

Iowa Code Section 317.13 requires a county to require permits for burning, mowing, or spraying of roadsides by individuals; these activities must be consistent with the adopted IRVM plan. This subsection only applies to roadside areas of a county that are included in an IRVM plan. Example permits are included in the appendix.

Counties may also choose to create permits for individuals to collect seed, plant native seed or plants, or manage the invasive species in roadsides bordering their property.

Public Outreach

Public Outreach thompsbb

Programs, partnerships, and events

Community events

Being present at public events and meetings can be an effective way to engage with the community. Some roadside managers have a booth at the county fair, for example. 

In odd-numbered years, the Iowa DNR holds Resource Enhancement and Protection (REAP) regional assemblies around Iowa; these assemblies are public meetings where information about REAP expenditures is presented and attending state officials listen to public feedback. Since 3% of REAP goes toward roadside vegetation management, roadside managers often attend to answer any questions about how those dollars are spent toward managing local roadside vegetation.

Presentations for community groups and schools

Groups that roadside managers have spoken at include local chapters of master gardeners, master conservationists, Sierra Club, Pheasants Forever, Rotary Club, and Kiwanis Club. The TPC roadside program manager has a PowerPoint template with information about the benefits of roadside programs that roadside managers can request and modify to suit their needs.

Roadside managers have also spoken to school groups. The TPC roadside program manager may have stickers available that have proven popular with schoolchildren. If your county has a root banner, inviting children to lay down next to the banner and see how their height compares can be a fun activity. Other educational activities related to prairie roots that meet Iowa educational standards are provided on the Educator Resources page of the Tallgrass Prairie Center website.

Press releases

Notify landowners and the public before major work is undertaken to maintain transparency. Some roadside managers also annually issue a press release about Iowa’s mowing law in April or early May. See an example press release in the Appendix.

Adopt-a-Prairie Program

A small number of counties have allowed landowners to partner with the roadside program to re-establish prairie vegetation in the roadside bordering their property. The county roadside manager removes the existing vegetation and replaces it with native vegetation if the landowner’s application is accepted; there does not have to be a road regrading project associated with the reseeding. 

Outreach materials and signage 

Signage for plantings

Use signage in plantings and high-quality areas to showcase native species. Signage lets the public know that a planting is intentional and not a bunch of “weeds.” Some counties prefer to print their own signs that include the county logo; Iowa Prison Industries is commonly used to print signs. Signs can include language such as “Roadside Prairie” or “Native Vegetation—Do Not Mow or Spray.” Counties that have an adopt a prairie program for residents and want a large number of signs can check with the LRTF coordinator to see if they can apply for an LRTF grant to purchase a large number of signs.

Other counties with a program obtain signs from the TPC roadside program manager, who uses LRTF funds to pay Iowa Prison Industries to print a certain number of signs each year. Check with the program manager to see what signs are available.

For landowners who want to know where they can get signs for their prairie plantings on private property, the Tallgrass Prairie Center maintains a webpage that directs people to different sources for signs.

Frequently asked questions

The TPC website includes a list of frequently asked questions and responses regarding roadside vegetation management.

Posters and guidebooks

The Living Roadway Trust Fund has free attractive posters available such as the Jewels of the Prairie poster set, a set of seven attractively illustrated guides to prairie plants and animals; the pollinator poster series; and a “roadsides of opportunities” poster. 

They also print spiral-bound guidebooks on how to identify pollinators, seedlings, and trees and shrubs that are free to the public. These materials are helpful to have available when tabling at community events and are available through the Living Roadway Trust Fund Publications website or by checking with the TPC roadside program manager, who may have some available.

Brochures: roadside management series

The TPC roadside program manager has brochures on roadside vegetation topics such as Iowa’s mowing law and landowner questions regarding roadsides. 

Brochures: how to restore prairie

The Center has a set of 10 brochures that provided detailed how-to technical information for topics such as collecting seed, designing seed mixes, site preparation, seeding, and maintaining plantings. The information is distilled from the Tallgrass Prairie Center Guide to Prairie Restoration in the Upper Midwest and can be downloaded on the Technical Guide Series part of the Tallgrass Prairie Center website.

Prairie root banners

The Center’s banners with life-size images of roots available for ordering capture people’s attention by conveying the tremendous density and size of prairie root systems. Approximately 14-foot long when rolled out, these portable and durable banners roll up for easy storage. Some counties or cities display them in the local nature center, library, or county courthouse. 

Prairie root specimens that are up to ten-foot long are an especially effective visual tool for public outreach. Similar to the prairie root banners, counties may display prairie root specimens at the local nature center, library, or county courthouse. To cover the cost of growing the roots over three years, the Center charges over $2,000 per root specimen plus shipping. 

Stickers 

The TPC roadside program manager may have stickers available that say “Roadsides for Wildlife” or that have the Iowa Roadside Management logo. 

Pull-up banner

The TPC roadside program manager may have pull-up banners with roadside vegetation information that can be borrowed for outreach events such as tabling at local community events.

Wall calendar

The TPC roadside program manager produces an annual wall calendar with a theme related to roadside vegetation management. For example, themes have included “Historic Roadsides,” “Celebrating Remnants,” and “Plant This Not That.” Wall calendars are mailed to roadside programs in the fall.

Lesson plans

Prairie roots 

A team of Iowa educators created a set of prairie roots lesson plans that align with Iowa Core standards for upper elementary and middle school students. Roadside managers can share the lessons with local educators or implement one of the lessons when visiting a local school.

Social media

A few roadside programs maintain their own social media account, but it is more common for programs to occasionally submit posts to a larger account such as the county conservation, county road department, county, or city social media account. According to social media best practices, posting at least two to three times a week is best for engagement and visibility. 

The TPC roadside program manager maintains an Iowa Roadside Management FacebookInstagram, and YouTube accounts for public outreach. 

Recordkeeping and cost data

Good recordkeeping is an important part of effective communication because it conveys transparency and builds trust. Accurate and up-to-date digital recordkeeping is a vital part of a roadside manager’s job, and should be started immediately. Roadside managers usually have to report to county boards of supervisors or a city council. Detailed, readily-accessible records provide an easy way to supplement reports like these with numerical values (including number of acres planted, volume of seed obtained through the Transportations Alternative Program, or the number of locations sprayed). Proof of accurate record keeping helps to justify the existence of a roadside manager’s position. 

Keeping account of costs and material-use is particularly useful, as it can be used as proof of the money and labor saving benefits of IRVM, particularly in reducing mowing and spraying. It is advisable to keep separate records for herbicide applications and other IRVM activities, as roadside managers are required to document every time they spray. 

As mentioned earlier, location-centric records are an especially useful tool. Many roadside managers have partnered with their county’s GIS division to develop useful tools for this purpose. 

Report about public perspectives on roadside vegetation

In 2016, Trees Forever received funding from LRTF to hire a marketing firm, Mindfire Communications, to research how Iowans, stakeholders, and legislators view the mission of the Living Roadway Trust Fund. Key survey questions included the following:

  • Who are our target audiences and where do we reach them?
  • What messages resonate with them?
  • How do we best drive engagement and support as well as perceptions of value in LRTF initiatives?

Read reports summarizing results.

Native Seed

Native Seed thompsbb
A pile of bags containing native seed

Native Seed for County and City Rights-of-Way

During most of the 1990s, counties and cities applied for grant money to purchase native seed to plant in their roadsides by applying for Living Roadway Trust Fund grants. However, starting in 1998 the TPC roadside program manager has been able to annually secure a single grant through the Federal Highway Administration (FHWA) to purchase a large quantity of seed (around 1,000–1,300 acres worth) and provide it to counties that request seed. In 2021, cities also became eligible to receive seed through this grant. Counties and cities receive the seed for free but provide the labor and equipment to plant and maintain the seed as an in-kind contribution. 

This large purchase has lowered the cost of seed per acre and has freed up more LRTF funds for other requests. The FHWA grant program has gone through several iterations: Intermodal Surface Transportation Efficiency Act, Transportation Enhancements, and Transportation Alternatives Program. It is currently called the Transportation Alternatives Set-Aside Program; a program manager in the Iowa DOT’s Systems Planning Bureau manages applications and grants for Iowa’s share of the Transportation Alternatives funds.

Every fall the TPC program manager emails seed request forms to the counties and cities that have an approved IRVM plan on file, counties and cities that anticipate completing an approved IRVM plan by June 1 of the following year and engineers and county conservation board directors in counties without a program (to ensure they are aware of the native seed as a benefit to having a program). Counties and cities estimate how much seed they will pick up the following spring. They have until December 31 of the year after picking up the seed, or a little over 1.5 years, to plant all of the seed that is picked up.

When counties and cities complete their seed requests, they must provide the location information for any sites that will be drilled or mechanically broadcast seeded using equipment that could cause rutting greater than six inches. Because there are Indigenous burial sites in some roadsides, the DOT archaeologist must coordinate with Tribal nations to determine if ground-disturbing activities might disturb burial sites or other cultural resources. Sites that will be hydroseeded or broadcast seeded using lighter equipment that do not disturb the soil do not have to be reviewed for cultural resources.

Counties may request a diversity mix (35–45 species) or a cleanout mix (20–30 species); both are suited to most roadside situations. The more inexpensive cleanout mixes are used more often in sites that are prone to silting in from adjacent farmland, which may require the county to periodically excavate the plugged-in ditch and reseed the area. The availability of these mixes means counties and cities might purchase directly from commercial seed vendors only when they wish to supplement the mixes or when a unique mix is desired for a special project.

Native Seed Categories

Native Seed Categories thompsbb

Use seed adapted to local climate and growing conditions

An example of a yellow tag identifying an Iowa source identified seed.

Yellow tag

Iowa yellow tag certified source-identified seed is highly recommended for roadside plantings. Because the Iowa Crop Improvement Association certifies that this Iowa seed originates from Iowa prairies, the region and climate to which it is adapted are known. This seed is often collected from multiple sites within a region of the state, giving it a broad genetic base and potentially making it adapted to a wider range of growing conditions. Buying yellow tag seed also reduces the risk of introducing new weeds to Iowa. Most of the seed provided through the FHWA grant is yellow tag seed.

Local ecotype

Local ecotype seed of Iowa or nearby origin that is not yellow-tag certified is also appropriate for roadside plantings and can be obtained from seed vendors by requesting “local ecotype” seed. Some counties establish their own local ecotype prairie grass and wildflower production plots with seed collected from prairie remnants within their county or region. It is important for this seed to be well cleaned and tested so it is known how much live seed is actually being planted.

Cultivars

Cultivars or cultivated varieties are generally not recommended. Cultivars are often derived from sources too far south and west of Iowa and so are adapted to a different climate and growing season. Most were developed for forage production and can be too aggressive in diverse plantings. Cultivars are available in only a limited number of species.

Sources of yellow tag species and related information can be found in the Iowa Crop Improvement Association’s Native Seed Directory. Additional native seed sources and information can be found in the Tallgrass Prairie Center’s Iowa Prairie Seed and Service Providers page.

Seed Labels

Seed Labels thompsbb

Learn to read them

Commercial seed labels contain a variety of information related to the quality of the seed. Some or all of the following items will be on the label:

  • Pure seed (purity) — Percent of material in the bag that is actually the desired seed
  • Inert matter — Percent plant debris or other materials that are not seed
  • Other crop seeds — Percent non-weed seeds
  • Weed seeds — Percent seeds considered weed species
  • Name and number of noxious weed seeds per pound
  • Germination — Percent of seed that will germinate readily in a germination chamber
  • Hard seed — Percent of seed that does not germinate readily because of a hard seed coat
  • Dormant seed — Percent of seed that does not germinate readily because it requires a pretreatment or weathering in the soil. (Some suppliers may combine hard and dormant seed on the label.)
  • Pounds pure live seed (PLS) — (# PLS) = (# bulk) x (% purity) x (% germination + % dormant)

A “TZ” (tetrazolium) % may also be on the label. Some native species’ seeds will not break dormancy for germination tests. These seeds can be biochemically tested using tetrazolium chloride (TZ). Living tissue is stained red, allowing analysts to determine the viability of non-germinated seed.

Seed stored for more than a year or grown/harvested “in-house” should be tested. The Iowa State University Seed Testing Laboratory and many private seed testing labs perform TZ tests as well as purity and germ tests, and will identify weed seeds in the sample. TZ test kits are also available.

The amount of weed seeds in a lot can vary widely; some of these amounts can seem high but are not necessarily cause for concern.


Tallgrass Prairie Center Insights

Three hundred and eighty noxious weed seeds per pound of native seed does seem high, but I sometimes get lots that have over 1,000 noxious weed seeds per pound. In my mind it's negligible since the actual weed seeding rate ends up being very low, and they are not necessarily all live seeds. The noxious weeds that show up in these tests are almost invariably annual agricultural weeds, so they will probably be gone within 2–3 yrs. The weed seed bank (at least in post-agriculture settings) is many orders of magnitude higher than these small amounts. Weeds listed as noxious on the tag are not necessarily Iowa noxious weeds either, so depending on who you buy from they might not even need to report it that way. In other words you may be seeding these weeds without knowing their identity anyway (they would be listed as a whole in the weed seed percentage). In this example, wild buckwheat is noxious in Minnesota but not in Iowa. I'm guessing they included it to cover bases for interstate commerce. While I wouldn't reject a lot like this, it would be worth keeping an eye on the planting. 
-Justin Meissen, Research and Restoration Program Manager, UNI Tallgrass Prairie Center, 2024

Seed Storage and Viability

Seed Storage and Viability thompsbb

Keep seed cool and dry

The viability of native seed deteriorates rapidly at high temperatures and high humidity.

General rule of thumb for seed storage: Temperature plus humidity should not exceed 100.

  • Most seed will last at least a year at 50° Fahrenheit and 50% relative humidity.
  • For each 10° increase in temperature, seed longevity is halved.
  • For each 1% increase in moisture content of the seed (not RH), longevity is also halved.

Example: Seed stored at 70° and 6% moisture content has only one-quarter the lifespan of seed stored at 50° and 6% moisture. Likewise, seed stored at 50° and 8% moisture content has only one-quarter the life span of seed stored at 50° and 6% moisture.

“Ideal” seed storage requirements vary with individual species, but most can be stored in a temperature- and humidity-controlled environment for at least a year without losing significant viability. Some IRVM programs have a dedicated seed storage facility. These insulated rooms and small buildings are rodent proof and include air-conditioning units and sometimes industrial dehumidifiers.

In the absence of a seed storage facility, seed should be stored in the coolest place possible. Air circulation can improve conditions in spaces without temperature/humidity controls. Short periods of heat (over 100° F) can be tolerated by most seeds, but long-term exposure can destroy the embryo.

Commercially produced seed has been properly dried before being bagged. Ideally, seed storage bags should be made of breathable materials such as cloth or woven nylon. Well-dried seed (8–14% moisture content, depending on species) — if  kept cool and dry — can be bagged and stored in garbage cans, plastic bags or other sealed containers without suffering damage from fungus or freezing. Watch for moisture build up.

Additional information on seed quality, processing and storage is found in The Tallgrass Prairie Center’s Native Seed Production Manual.


Roadside Manager Insights

We’ve noticed Liatris grows very poorly unless it’s dormant seeded shortly after harvest. Perhaps it loses viability or vigor when stored over winter, or maybe it needs to be stored at a higher humidity than most seed
-Jim Uthe, James Devig, Dallas County, 2024

With a little increase in rate per acre, I think generally year-old seed can be used with no problem. We use older seed (2–3 years) at whatever rate it takes to use it up over the course of the season. I add a reduced rate of new seed to cover any loss of germination. 
-Linn Reece, Hardin County, 2010

Seed Mixes

Seed Mixes thompsbb

Take advantage of prairie diversity

Native roadside seed mixes need to include species adapted to a wide range of growing conditions, from wet to mesic to dry. To outcompete weeds, the mix should also include species that occupy different ecological niches within the planting, grass species and broadleaf species, warm-season and cool-season species, tall plants to shade out thistle seedlings, and small plants to fill in underneath.

When working in narrow ditches, such as those found within a 66-ft. right-of-way, it is most efficient to design one mix that includes species for a wide range of site conditions — from the gravelly, well drained soils at the top of the slope, to the heavy, saturated soils at ditch bottom. Apply the same mix over the entire area and let it sort itself out. Wider rights-of-way may have wet or dry areas large enough to justify designing and planting a seed mix specific to those spots.

To achieve a well-rounded mix with all the benefits native vegetation has to offer, include species from each of the following functional groups. The Tallgrass Prairie Center’s Designing Seed Mixes technical guide and seed calculator can also be helpful for designing seed mixes.

A well-rounded native seed mix will include species from each of these groups:

Quick-establishing

Some native species develop faster than others. These are important for early erosion control and provide positive PR while slower species establish. 

  • Canada wildrye (Elymus canadensis)
  • Black-eyed Susan (Rudbeckia hirta)
  • Rough dropseed (Sporobolus asper)
  • Partridge pea (Cassia fasciculata)

Warm-season grasses

Roadside plantings rely heavily on these prominent members of the native plant community. These grasses continue to grow through the hot summer months. They provide long-term erosion control and good fall color.

  • Big bluestem (Andropogon gerardii)
  • Indiangrass (Sorghastrum nutans)
  • Switchgrass (Panicum virgatum)
  • Side-oats grama (Bouteloua curtipendula)

Cool-season species

Plantings are strengthened by a species component that greens up early in the spring. These plants provide late-winter/early-spring erosion control and occupy the niche sought by non-native, cool-season competitors like smooth brome.

  • Canada wildrye (Elymus canadensis)
  • Virginia wildrye (Elymus virginicus)
  • Western wheatgrass (Agropyron smithii)
  • Sedges (Carex spp.)

Legumes

The prairie flora includes many legumes that thrive in roadside plantings. They fix nitrogen and improve habitat.

  • White wild indigo (Baptisia leucantha)
  • Round-headed bush clover (Lespedeza capitata)
  • Showy tick-trefoil (Desmodium canadense)
  • Canada milk vetch (Astragalus canadensis)
  • Purple prairie clover (Dalea purpurea)

Showy and easy

These species establish readily, are relatively inexpensive and create masses of color noticeable at 65 mph. They are crowd pleasers. 

  • Gray-headed coneflower (Ratibida pinnata)
  • Ox-eye sunflower (Heliopsis helianthoides)
  • Wild bergamot (Monarda fistulosa)
  • New England aster (Symphyotrichum novae-angliae)
  • Black-eyed susan (Rudbeckia hirta)

Showy

The following species cost a little more or are harder to establish but still add important color and habitat.

  • Butterfly milkweed (Asclepias tuberosa)
  • Prairie blazing star (Liatris pycnostachya)
  • Compassplant (Silphium laciniatum)
  • Pale purple coneflower (Echinacea pallida)
  • Stiff goldenrod (Oligoneuron rigidum)

Early bloomers

It’s relatively easy to extend a planting’s blooming season into the fall. Spring color is harder to come by. The following plants provide the earliest color visible from the road.

  • Ohio spiderwort (Tradescantia ohiensis)
  • Foxglove beardtongue (Penstemon digitalis)
  • Golden Alexanders (Zizia aurea)
  • Large-flowered beardtongue (Penstemon grandiflora)

Wet species

Upland species dominate roadside seeding mixes. Species adapted to wet areas are needed for moist ditch bottoms.

  • Bluejoint grass (Calamagrostis canadensis)
  • Swamp milkweed (Asclepias incarnata)
  • Dark green bulrush (Scirpus atrovirens)
  • Sneezeweed (Helenium autumnale)
  • Mountain mint (Pycnanthemum virginianum)

A note about tall grasses and non-native perennials

For visibility and safety, tall grasses — such as big bluestem and Indiangrass — should not be planted at intersections or driveways. Omitting these grasses throughout the remainder of a planting, however, will limit its adaptability. Big bluestem and Indiangrass are versatile, adapted to conditions from medium-dry to medium-wet. Short native grasses, on the other hand, are generally adapted only to dry sites.

Non-native perennials — such as tall fescue, perennial rye, crown vetch, and birdsfoot trefoil — are very competitive and will persist to the point of adversely affecting survival of native seedlings. These species should not be used in permanent or temporary mixes for sites planted to natives.

Seed mixes for shoulders

Native species are not used on the shoulder. Examples of seed mixes that withstand repeated mowing and are well-suited to shoulder conditions follow.

  • 50% Kentucky, 31% fescue, and 50% perennial rye

  • 45% Kentucky, 31% fescue, 45% perennial rye, 6% medium red clover, and 4% alsike clover

  • 35% Fawn fescue, 35% perennial rye, 20% timothy, and 10% alfalfa, or hairy vetch


Roadside Manager Insights

Keep in mind in most situations we’re not recreating a diverse prairie. We’re stabilizing the roadside with native plants.

-Joe Kooiker, Story County, 2024

Aspect/shading sometimes need to be taken into account, especially on small plantings or problem areas. In shaded areas, we use savanna species in the mix. If there’s a lot of shade, we may plant a nonnative, cool-season mix. 

-Jim Uthe, James Devig, Dallas County, 2024

We use local ecotype hand-harvested forbs and combined seed from our native seed nurseries to add diversity to our roadside seed mixes

-Joe Kooiker, Story County, 2024

Try to tailor your mix so the ROW has color all year long.

-Joe Kooiker, Story County, 2024

Depending upon soil type, we may use up to a 1.5x the rate of native seed to help speed establishment and stabilization. 

-Jim Uthe, James Devig, Dallas County, 2024


Seeding rates

Put down enough good seed to get timely vegetative cover and ensure planting success

Steeper slopes require heavier seeding rates. To get adequate erosion control, it’s more affordable to increase the amount of grass in the mix than to increase forbs. The result is that roadside plantings tend to have a higher grass to forb ratio than other prairie restorations. No matter how much native grass seed is put down, at least a 25% forb component is recommended to achieve adequate diversity and long-term stability. A 50% forb component is considered adequate for a fairly diverse planting. Some counties—especially those with their own forb seed plots—may exceed 50% for intersections and other highly visible plantings.


Grass to forb ratio

To get adequate erosion control, it's most affordable to increase the amount of grass in the mix. No matter how much native grass seed is put down, at least 25% forb component is recommended to achieve adequate diversity and long-term stability. 50% is better.


Seeding rates are calculated in one of two ways:

  • Seeds per square foot 
  • Lbs./acre

Though frequently used, lbs./acre is not a precise way of measuring the number of seeds planted since seed weights vary greatly between species. For example, one ounce of compass plant contains 660 seeds, while one ounce of black-eyed Susan contains 92,000 seeds. When accurate calculations are desired, use seeds/ft.

Seeding rates for roadside mixes are determined by slope and – to a lesser degree – seeding method. Budgets can also be a factor. The following chart provides general guidelines – a good idea of how many seeds should be put on the ground.

Minimum recommended seeding rates

 Wildflowers Native grasses
Level sites:2 lb./A or 10 seeds/per square foot

+

7.5 lb./A or 30 seeds/per square foot
3:1 slopes3 lb./A or 10 seeds/per square foot

+

11 lb./A or 45 seeds/per square foot
2:1 slopes4 lb./A or 20 seeds per square foot

+

15 lb./A or 60 seeds/per square foot

These rates apply to drill seeding, broadcast seeding and hydroseeding (two-pass method). When hydroseeding with seed mixed in the slurry (one-pass method), increase rates by 15–30% to compensate for seed hung up in the mulch. (Note: Under real working conditions, even the best attempts at measuring seed quantities in the field will not be perfectly precise.)

The Iowa Prairie Seed Calculator will help you if you would like to create custom mixes. 

Seeding

Seeding thompsbb

There is no single, correct way to seed native vegetation and there is no substitute for experience. Successful planting is the result of getting familiar with the equipment and developing the “art” – one’s own way of working with natives. As a wise man once said: “It won’t grow in the bag.” The message:

Don’t worry so much about how to plant it. Get out there and start seeding.

Basic steps to successful seeding:

  • Use good seed.
  • Place seed in direct contact with the soil.
  • Don’t bury seed more than ¼ in. deep.
  • Pack seed tightly to the soil.
  • Include erosion control measures where necessary.
  • Mow weeds during the first growing season.
  • Conduct prescribed burns every three to five years.

Timing

Timing thompsbb

May and June are ideal seeding months, but road construction projects are rarely ready for seeding at this time. The following seeding calendar provides suggestions for protecting slopes and improving seeding success throughout the year.

January to mid-March

Winter months occasionally present windows of opportunity for frost seeding, a practice that originated as a way of incorporating seed into the soil when a native grass drill was not available. Seed is spread over bare soil made friable (loose or porous) by a cycle of freezing and thawing. Results can be good, but opportunities can be brief.

  • Be ready to jump on it. 
  • Include oats as a cool-season nurse crop.
  • Do not frost seed on areas covered with ice or snow.
    • Occasionally native seed is sown on top of snow. Technically this is not frost seeding, but can be an effective seeding method on relatively level sites.
  • Frost seeding on slopes is not recommended.

Late March through April

If site conditions permit (ground not frozen or too sloppy) this can be a good time for seeding. Warm-season grasses won’t germinate until soil temperatures reach 60 degrees Fahrenheit. Include oats as a cool-season nurse crop.

May and June

This time of year provides the best soil temperature and moisture conditions for germination and survival of warm-season species, including most prairie grasses and wildflowers.

July and August

Although every county can point to successful plantings during these months, hot, dry summer conditions are generally less favorable for planting natives. Consider a temporary seeding at this time, with the permanent, native seeding in the fall or the following spring.

If natives must be seeded now:

  • Drill, rather than hydroseed, for maximum seed to soil contact.
  • Increase seeding rate 25%.
  • Include appropriate nurse crop.
  • Mulch with straw, and crimp or tack straw into place.

September and October

Native seed germinating this late in the season is unlikely to develop enough root reserves to overwinter. Yet some of these plantings do succeed, maybe because a lot of the seed does not germinate until spring. Research is needed.

  • Erodible sites must be stabilized with winter wheat.
  • Increase seeding rate 25%.

November and December

Dormant seeding, considered a good option on level ground, is more complicated on erodible slopes. Cover crops seeded this late won’t provide erosion control until spring. The majority of native seed will remain dormant over winter. While some forb species do better when dormant seeded, some of the native grass seed planted at this time will deteriorate over winter.  

  • Erodible sites must be stabilized with winter wheat.
  • Increase seeding rate 25%.

Roadside Manager Insights

Timing is everything, watch the weather and don’t just seed a site to get it off the list.

-Joe Kooiker, Story County, 2024

Ideally, we begin dormant seeding in October or November once the 4” soil temperature reaches 50 degrees, but if erosion is a concern or there is an issue regarding a regulatory permit, we will seed earlier and may increase the seed rate some and hope for dormant seed.

-Jim Uthe, James Devig, Dallas County, 2024

I try not to seed in August, September, or early October. I prefer to wait until November, then drill into a cover crop and mow the following spring. If weather conditions deteriorate in November, I can still seed in the spring. However, there are many factors that can influence when seeding gets done including size of project, time available, topography, etc. Small sites and those that are not conducive to drilling typically get seeded as soon as possible.

-Wes Gibbs, Jones County, 2024

I don’t intentionally wait to frost seed. I might consider it, but only on flat areas in perfect conditions. 

-Wes Gibbs, Jones County, 2024

Site Preparation

Site Preparation thompsbb

Site preparation enhances seed to soil contact, helps ensure proper planting depth and can even provide erosion control.

Prior to working the site

  • Walk the site looking for gullies, culverts and other hazards (e.g., logs, stones, stumps, etc.).
  • If weed growth is excessive, mow and disk stubble into the soil, if possible.
  • Check with utility companies before disking.
  • Calculate the size of the area to be planted and the amount of seed it will take.
  • Size up the watershed and the site’s erosion potential.

Seedbed preparation for drill seeding

Ideal seedbeds are friable, firm and smooth

  • To reduce erosion, don’t smooth up the site until just before planting.
  • Relatively level sites can be worked with a disk, chain-tooth harrow or similar equipment.
  • To avoid excessive clodding, don’t work the site while it’s too wet.
  • Cultipacking can help firm the seedbed and reduce clods.

Seedbed preparation for hydroseeding

Seedbeds can be left rougher to reduce erosion.

  • Steep slopes can be ripped with a wide-track dozer.
  • Directional tracking can be used to interrupt water flow.
  • Work the site perpendicular to the slope to interrupt water flow.

Heavily compacted soils

  • Try to work the site to a depth of three inches.
  • A heavy disk might be necessary.
  • Some sites may need to be worked with long bulldozer tines. 
An illustrated bulldozer creating grooves in a sloped roadside.
This diagram illustrates directional tracking: dozer treads create grooves perpendicular to the slope.

Getting your seeds to grow is a priority, try to get good seed to soil contact when possible.

-Joe Kooiker, Story County, 2024

For hydroseeding we prefer the site to be rough and a little soft. We seed immediately after the construction equipment has left, with no additional seedbed preparation. The rough texture keeps the seed in place and the softness allows for better root penetration. However, for drill seeding, firmness is the most important factor. It is easy for seed to get buried too deep in soft seedbeds, either during or post planting. 

-Doug Sheeley, Dallas County, 2024

Cover Crops

Cover Crops thompsbb

There are two kinds of cover crops. Cover crops planted along with the permanent seed mix are called nurse crops or companion crops. Those planted by themselves pending a better time to plant the permanent mix are referred to as temporary seedings or stabilizer crops.

Cover crops help hold the soil and are recommended on slopes 3:1 or greater. Oats Avena sativa, annual rye Lolium multiflorum* and winter wheat Triticum aestivum are excellent cover crops because they are inexpensive, easily established and not overly competitive.

Recommended nurse crops/companion crops (planted with the native seed) — per acre

‌Spring

  • 1.5 bushels oats or
  • 1 bushel oats and 5 lb. annual rye

Summer

  • 2 bushels oats or
  • 1 bushel oats and 10 lb. annual rye

‌Fall

  • 30 lb. winter wheat

Recommended Temporary Seedings/Stabilizer Crops (native seed to follow in the spring) — per acre

Summer

1 bushel oats plus 10 lb. annual rye and one of the following warm-season species:

  • 5 lb. piper sudangrass
  • 10 lb. millet (Japanese or Pear varieties)
  • 30 lb. sorghum (grain or forage)

‌Fall

  • 20 lb. annual rye or
  • 60 lb. winter wheat

Caution: For native plantings, winter wheat is preferred over winter rye. Winter rye is taller, more persistent and possibly allelopathic, chemically inhibiting the growth of wildflowers. There are many kinds of rye: annual rye (Lolium multiflorum); perennial rye (Lolium perenne) and winter rye, cereal rye and grain rye (all names for the same plant, Secale cereale). Do not seed piper sudangrass, millet or sorghum too heavily. One good rain can cause mass germination. Piper sudangrass may cause concern among landowners as it is sometimes confused with shatter cane.

Cover crop conversion chart

SpeciesPounds in a bushelSeeds in an ounceSeeding at 1 bushel/A results  in
Oats3291010 seeds per square foot
Winter wheat6093720 seeds per square foot
Annual rye-12,710Seeding at 10 lb./A results in 46 seeds per square foot

 

Cover crops are as much for public perception as they are for erosion control. Having your plantings turn green in a timely fashion is essential for a program’s success.

-Joe Kooiker, Story County, 2024

We use a bushel per acre of winter wheat as a nurse crop when dormant seeding with a hydroseeder. In the spring when hydroseeding, we use a bushel of oats if the soil prep, soil moisture forecast are appropriate. We may continue to use oats through summer in good soil that’s adequately prepped and if moisture is in the forecast. We will blend in annual rye and/or even pearl millet or may substitute the oats for these species as soil conditions and forecast become less favorable.

-Jim Uthe, James Devig, Dallas County, 2024

In addition to increasing our native seed rate on very steep slopes, we also increase our cover crop rate, we essentially do this by applying more material out of the hydroseeder as concern for erosion increases.

-Jim Uthe, James Devig, Dallas County, 2024

In typical Iowa soils, fertilizer and plant growth hormones aren’t needed. However, we’ve used various growth stimulants along with starter fertilizers and various other amendments on steep slopes with poor soil, and have had very good results. It’s cheaper to quickly establish a cover crop than to spend the time and resources repairing or redoing a project. It’s also good PR with the engineering staff and public to see a quick green-up. Again, we only use this practice on areas of very poor soil with a lot of erosion potential, or to protect a high-dollar project.

-Jim Uthe, James Devig, Dallas County, 2024

The majority of our regraded slopes are steep. I regularly use 2.5 bushels of oats, 6 lbs. of annual rye and 3 lbs. of timothy along with the permanent seed mix. This provides a better chance of stabilizing the slopes while the permanent seeding establishes, and I haven’t noticed any detrimental effect to the planting’s long-term success. 

-Linn Reece, Hardin County, 2011

The nurse crop can be added to the slurry in the second pass with good success. Wheat and oats are very difficult to keep in suspension in pure water, so it’s better to include in the mulch in the second pass.

-Wes Gibbs, Jones County, 2024

On large, contracted projects we fertilize the cover crop to DOT specs; the flush of weeds has usually subsided by the time we plant natives in the fall or following spring. We do not use fertilizer when hydroseeding. 

-Wes Gibbs, Jones County, 2024

When broadcasting in light tillage we use some, but sparingly. I wouldn't recommend fertilizer with natives, but it does help cover crops planted in nutrient-deficient soils. 

-Wes Gibbs, Jones County, 2024

I have used several different cover crops from oats, winter rye, buckwheat, perennial rye, and going to experiment with sorghum grain and Sudan grass, and mellites for summer ditch cleanouts and other projects. I will utilize these species because they are drought tolerant, and they are fast growing. These are things that we are all battling with in the ROW’s. For rates of current use – oats 30 to 40lbs/ac, winter rye 1bu/ac, perennial rye 10lbs/ac I keep this thin with the rye and oats to get some fast green on projects but then the natives can out compete them in the long run, and buckwheat 10 to 20lbs/ac on summer projects keep it on the lighter side with oats and perennial rye because they have a large leaf and can cause shade out of natives until a mowing on a first year seeding. I like buckwheat in my summer blend because it is fast growing and drought tolerant.

 Most of these cover crops are broadcast seeded, however I have done some drilling and mixed it in with the hydroseeder as a method of seeding. I have seed success with all application methods.

-Griffin Cabalka, Black Hawk County, 2024

Mixing Seed

Mixing Seed thompsbb

Native seed can be ordered pre-mixed. If species come individually bagged, they will have to be mixed thoroughly. Mechanical seed mixers are available. Otherwise hand mix as follows:

  • On a calm, dry day seed can be mixed outdoors on a smooth, concrete surface. Otherwise select a well-ventilated building with a hard, smooth floor.
  • Wear a dust mask and safety glasses.
  • Prop the door open wide and turn on the exhaust fan.
  • Measure out the seed with a scale and dump it in piles.
  • Mix seed with scoop shovels.
  • After mixing, put seed in trash cans for hauling to the site.
  • Seed that won’t be planted right away must be kept cool and dry.

Seeding Methods

Seeding Methods thompsbb

There are three seeding methods: drill seeding, broadcasting and hydroseeding. Each has advantages and disadvantages.

Drill seeding

Seeding with a native grass drill is the preferred method on level rights-of-way. Drilling is a one-step process and is quicker and cheaper than hydroseeding. Drills do a better job establishing native grasses and produce faster results overall.

Drills do not work well on slopes. At 3:1 or steeper, the drill will try to slide sideways causing the disk openers to dig in and bury the seed. Projects with silt fences present another challenge; maneuvering a tractor and drill around these fences is difficult.

Drill seeding tips

  • Calibrate the drill in the shop and set the rate a little lighter than what you actually want.
  • Bouncing over the ground, a drill set at 6.5 lb. to the acre might actually seed 8 lbs. to the acre.
  • When planting very clean seed with an older drill, use a filler to slow it down. Bulk-harvested seed or fluffy little bluestem works well.
  • For good seed distribution, use the small seed box for fine seed and the fluffy seed box for grasses, large forb seed and seed that hasn’t been well-cleaned. Alternatively, sprinkle a portion of the forb seed on top of the other seed in the drill’s middle hopper, then add more forbs every other round or two.
  • Do not plant native seed deeper than ¼ in. Most native seed is small and lacks the energy to emerge if planted too deep.
  • The trash plow attachment on a native grass drill should just scratch the surface. If it’s making furrows, it’s planting too deep.
  • For uniform coverage, drill seed at a light rate and go over the area twice.
  • Multiple passes packs the seed well and creates more rills that hold seed and interrupt water flow.
  • To prevent seed from being buried too deep, disconnect the lower end of the drill’s seed tubes. Some of the seed will land on the soil surface and not be buried in the furrow. Some people prefer to unhook only every other tube. Others unhook only the tubes coming from the small seed box.

Hydroseeding

Hydroseeding is ideal for bridge approaches, cleanouts, culverts and wet or steep slopes. In most cases, the entire project can be hydroseeded from the shoulder. Other hydroseeding advantages — hydromulch reduces soil erosion; the risk of seeding too deep is eliminated; colored mulch on the soil makes a positive impression on the public.

Filling the hydroseeder takes time, so drilling or broadcasting are usually quicker for larger projects. Other hydroseeding disadvantages — mulch is expensive and can double the cost of a seeding, the seeding rate is harder to control, and hydroseeding is strictly a bare-ground application.

Hydroseeding tips

  • It’s best to seed after a rain, not just before. Seed and mulch stick better on moist soils. Some moisture is captured under the mulch. Mulch needs time to set up before it rains.
  • Increase overall seeding rate by 25% to compensate for seed damaged going through hydroseeder mechanics and for seed that gets hung up in the mulch.
  • The “shadow areas” behind larger dirt clods sometimes get no seed. For better coverage, try to seed in two passes, one from each direction. Seed lightly — so the seeding rate is not doubled — at 7 to 8 mph, with flow rate reduced.
  • An 800-gallon hydroseeder is the minimum recommended size. A 1,500-gallon hydroseeder can cover 1/3 acre per load. With a machine of this size, seven 50-lb. bales, or 350 lb. of mulch per load, yields about 1,000 lb./acre.
  • Seed the area farthest from the road first.
  • On steep slopes, try to embed the seed by using a more concentrated stream and holding the gun at a sharper angle.
  • For the sake of efficiency, most county roadside managers apply seed and mulch in one pass. The “two-pass method” — seed applied first, hydromulch to follow — results in better establishment since more seed is in direct contact with the soil.

Hydromulching rates

  • 1,000 lb./acre — a token amount to help carry the seed and show what area has been seeded
  • 2,000 lb./acre — appropriate for most 3:1 slopes
  • 3,000 lb./acre — very heavy rate for long, steep slopes

Broadcast seeding

Broadcast seeding is a viable option now that commercially available native seed is cleaner and less fluffy than it once was. When applied with broadcast seeding equipment, this debearded seed flows better and slings farther and truer than in the past.

Broadcast seeding tips

  • Broadcasting finer-seeded species prevents them from getting buried under too much soil.
  • For very clean seed, the Vicon broadcaster can be adjusted down to the “nth” degree.
  • For fluffy seed just open the gate a lot wider.
  • A broadcast seeder on a 3-point is more compact than a drill and easier to get in and out of ditches.
  • Broadcasters can be backed up to silt fences to sling seed on both sides.

Hand seeding

Scattering seed by hand followed by light raking is very effective for smaller sites and prevents fine seed from being planted too deeply.

  • To improve distribution, mix the seed with some kind of carrier. Sand is best. Kitty litter or oats are also used.
  • Mix the seed and carrier in a bucket and scatter it over the site by hand.
  • Many wet prairie species have fine seed and should be seeded this way.

Packing the seed

Packing seed tightly to the soil ensures a more consistent flow of moisture from the soil to the seed. The result is better germination and better seedling survival.

  • Packing is most important after broadcast seeding, but is always beneficial.
  • A 4-ft. cultipacker section on a 3-point is very effective and will go places the tractor and drill can’t.

Roadside Manager Insights

We lightly disk the seedbed before hydroseeding, if possible; cultipack after we seed; then apply mulch (two-pass method).

-Joe Kooiker, Story County, 2024

The hydroseeding is a great method of seeding, but not always necessarily the tool for the job.

-Joe Kooiker, Story County, 2024

When filling a hydroseeder from a creek, know your source. Don’t fill from an area with invasives (e.g., purple loosestrife).

-Jim Uthe, James Devig, Dallas County, 2024

Filling near the site with a trash pump has drastically improved the efficiency of the process. We mounted the pump on the seeder, so we simply drop a fill line into the water and turn on the pump.

-Josh Brandt, Cerro Gordo County, 2010

When hydroseeding, be sure to mix seed thoroughly in the water, both initially and periodically during application. Our Finn hydroseeder can reverse the mechanical agitation, which is helpful.

-Jim Uthe, James Devig, Dallas County, 2024

We have better germination with lighter hydromulch rates (400–500 lbs./acre).

-Dave Sedivec, Chickasaw County, 2010

There’s been some concern about high mulch rates affecting seed germination. I don’t think that’s an issue with large grass seeds, and even small seeds aren’t affected when dormant seeding with a high mulch rate since the mulch softens and breaks down over the winter. The seed can’t germinate if it’s washed away, so use enough mulch to get the job done right. 

-Jim Uthe, James Devig, Dallas County, 2024

When mixing seed, we mix 10 acres worth of the fluffy grass (sideoats, big blue, Indian, little blue and Canada wild rye) and compass plant and put it in large, plastic garbage cans. Then we mix 10 acres worth of the remaining forbs in a large Rubbermaid tote and put the two slick grass seeds (rough dropseed and switch) in a 3rd tote. Our fluffy grass rate is around 10–12 bulk lbs/acre, our forbs are usually around 3–4 and slick seed is around 2 lb./ac.

-Jim Uthe, James Devig, Dallas County, 2024

When hydroseeding, we bump these rates an extra 30 to 50% at times depending upon site conditions and current climatic factors. We pretty much always seed with mulch and we typically use 1,500 lbs. of wood fiber mulch per acre. Our 3,300-gallon unit seeds about 0.9 acres pretty well with 1,350 lbs. of mulch in it (3,600 gal. of material per acre). Some people I know put 1,500 lbs. in a 3300 gallon seeder and seed a full acre, but we always seem to run a little short doing it that way. 

-Jim Uthe, James Devig, Dallas County, 2024

Don’t trust your drill to meter your seed. Know your acreage and equally distribute the seed.

-Wes Gibbs, Jones County, 2024

When hydroseeding, you initially have to know how much area you are covering with a full load. With our Finn T-90, I cover a third of an acre per load. That may be more than is recommended for that size machine, but it means fewer loads per job and quicker to finish. With our 22-foot wide ROWs (average), we travel 660 feet to make that 1/3 of an acre. With practice you can become pretty accurate — arriving at 660 feet with an empty hydroseeder. If we use UNI’s recommended rates, then big bluestem at 1.5 lbs per acre, for example, uses 0.5 lbs per load. We weigh out the amount of each species needed for a 1/3 of an acre and put it in one bag ahead of time. Then we can just dump the bag in each load. This holds true for the nurse and temporary crops as well. 

-Linn Reece, Hardin County, 2011

Converting Non-Native Roadsides to Native

Converting Non-Native Roadsides to Native thompsbb

Occasionally a landowner will contact the county IRVM program to request a native planting adjacent to his/her property. If the site is conducive to a successful native planting, some counties accommodate these requests. Converting non-native vegetation to native requires eliminating the existing vegetation, usually by application of glyphosate. Cool-season grasses such as brome, fescue and bluegrass can be persistent and might require more than one application.

  • Kill existing vegetation with a 2% solution of glyphosate in April or May.
  • If thistles and other broadleaves are present, apply a Transline/Telar mix the fall prior to glyphosate in the spring.
  • Apply the herbicide when existing vegetation is green and growing but no more than 12 in. tall.
  • If there is still green grass after ten days, apply the herbicide a second time.
  • Consider keeping the top 4 ft. of the foreslope unsprayed, leaving it stabilized with mowable, cool-season grasses.
  • A native grass drill is most effective for planting into the dead stubble, disturbing the dead turf as little as possible while getting seed in direct contact with soil.
  • Keep the entire planting mowed during the first growing season because weeds will likely be released once the existing cover has been destroyed.
  • In subsequent years, spot-spray weeds as they appear.

Establishment mowing

During the first growing season, native seedlings remain small and can suffer losses due to competition by tall, thick weeds.

  • Mow the planting three or four times during the first growing season.
  • Don’t wait until the weeds are too tall.
  • A mowing height of 4 in. is good but to avoid scalping, 8 in. is better.

Evaluating new plantings

First-year native seedlings are small, making them hard to find and even harder to identify. As a result, people often worry or assume the planting is a failure.

  • If the success of a seeding is being challenged, hire a botanist to look for seedlings.
  • Unless a planting is washed out by heavy rains, allow two full growing seasons before giving up and starting over.

Erosion Control

Erosion Control thompsbb
Roadside management staff unfurl an erosion control blanket in a roadside ditch.

Erosion control protects water quality, maintains the structural integrity of the roadway, protects germinating seed and helps counties and cities comply with National Pollutant Discharge Elimination System (NPDES) Phase II regulations. It is among the most important goals of a roadside program. Permanent vegetation is the long-term solution, but short-term erosion control is necessary to protect exposed soil while vegetation matures.

Types of erosion

Soil erosion can occur through different processes. Those of greatest concern to a roadside manager are splashsheet and rill erosion on slopes and channel erosion in concentrated flow areas.

  • Splash erosion occurs when raindrops dislodge exposed soil particles. These particles settle in soil pores and when dry, form a crust, reducing infiltration during subsequent rains.
  • Sheet erosion occurs in heavier rains on uniformly smooth soil surfaces. Dislodged particles become suspended and are transported downslope.
  • Rill erosion occurs when slight differences in soil surface elevation cause runoff to concentrate and form a pattern of cuts or rills.  It is more likely to occur than sheet erosion since slopes are rarely uniformly smooth.
  • Channel erosion occurs in concentrated flow areas and is caused by downward scour due to flow shear stress. Many, if not all, roadsides are conduits for concentrated flow.

Planning for erosion control

Erosion control objectives should be considered in the planning stage of each roadside project. Many factors affect a site’s erosion potential. Some also affect how quickly vegetation will establish and provide stabilization. The following interconnected factors should be analyzed to determine what, if any, erosion control practices are necessary:

  • Time of year (How long will soil be exposed?)
  • Soil type and fertility
  • Slope length, grade and aspect
  • Off-site surface flow onto project area
  • Type of seed mix (Warm season establishes slower than cool season.)
  • Weather forecast

Other considerations: the consequences of failure and the presence of sensitive areas (e.g., wetlands, sensitive waterways and critical habitats for threatened and endangered species).


Erosion control and IRVM

Some IRVM programs will be more involved in erosion control than others. Sediment control and long-term erosion control may be the responsibility of other departments or contracted out.

All IRVM programs will be responsible for short-term soil protection provided by proper site preparation, nurse/stabilizer crops and mulches.

Erosion Control

Erosion Control thompsbb

General short- and long-term erosion control techniques are outlined below. The erosion control industry has many useful websites with up-to-date technical specifications and guidelines. A list is provided at the end of the chapter. Take advantage of these resources and other educational opportunities to stay abreast of this rapidly evolving industry.

Soil preparation

Strike a balance between an ideal seedbed and maximum erosion control. Firm, friable soil surfaces — recommended for seeding — can be susceptible to erosion. Loose, rough soil surfaces provide better infiltration and slow runoff.

Surface roughening practices, such as directional tracking and grooving, slow runoff by creating depressions or grooves perpendicular to the flow. On steep slopes, these practices must be used in conjunction with other methods, preferably hydroseeding. 

Directional tracking

Driving a bulldozer or other tracked vehicle up and down a slope leaves depressions perpendicular to the slope. (Driving a tracked vehicle across the slope can increase erosion.) Tracking may not be appropriate on clayey soil since compaction can inhibit vegetation establishment, and severe compaction can even prevent no-till drills from penetrating the soil. Concerns regarding compaction decrease when hydroseeding or broadcasting during the dormant season, since freezing and thawing will loosen the soil.

Grooving

Pulling a disk or ripper behind a tractor or dozer, or back-dragging a toothed bucket with a loader across a slope creates a series of ridges and grooves. Grooving can be more effective than tracking because the depressions are usually deeper and the soil is left in a looser state. Many implements can be used.

SUDAS (Statewide Urban Design and Specifications) specifies grooves be no more than 15 in. apart and 3 in. deep, though groove depth is subject to debate. Deep grooves improve erosion control, but increase the likelihood of seed becoming buried too deeply to germinate. Seeding method will help determine the appropriate groove depth. One-step hydroseeding is best over deeper grooves since mulch keeps seed near the surface. If seed is not incorporated in a slurry when planted, lighter grooving is recommended.

Mulch

Mulch helps prevent splash erosion and holds seed in place by absorbing rainfall impact and binding soil particles together. Mulching is accomplished by blowing on straw or by hydromulching.

Straw

Dry cereal straw — free of noxious weed seed — can be applied alone or on top of seed to provide short-term erosion protection, conserve moisture and suppress weeds. Typically oats or wheat straw is used — blown on at a rate of 1 to 1½ tons per acre. Straw applied evenly at the correct rate will allow approximately 50% of the soil to be visible. If applied too heavily, seed germination may be affected. Some bale processors can be adjusted to make shorter or longer mulch — longer is better.

To keep straw mulch on site, it must be crimped or tacked in place. Areas accessible to ground-driven equipment can be crimped. Crimpers (a.k.a. mulch tuckers or mulch discs) are mounted on a 3-point and pulled with a front-wheel assist tractor. Test runs are necessary to ensure the crimper wheels go into the soil at least three inches — enough to anchor the straw. Properly anchored straw mulch will stand up straight and look similar to oats mowed high.

Tacking is accomplished by adding tackifier to water in a hydroseeder and applying evenly until the straw is wet, but not running off. This dries and acts as a glue to hold the straw in place. Tackifier rates vary with brand and are provided on the bottle in lbs. per acre. If too much tack is added, the mixture will get slimy and prevent the pump from priming. 

Some IRVM programs use prairie hay — harvested from plots or plantings — in place of straw mulch. Application method and rates are similar to straw, though rates may vary depending on the dominant species in the hay. Fewer bales will be necessary because the hay weighs more than straw.


Roadside manager insights

We use wheat straw. It seems to be longer than oats straw and is typically the same price. I have worked with a local contractor who brings up Kansas wheat straw. We have also used Iowa Certified weed seed free straw. 

-Wes Gibbs, Jones County, 2024

With oats or wheat straw, I’ve used seed-bearing stalks to my advantage; it can work as a good cover crop. 

-Ben Hoskinson, Mahaska County, 2011

We use an agricultural-type bale processor (no cannon). I use the rate of 1.5 T/acre as a minimum when planning. Just be sure you aren’t blanketing over your seed. You should be able to barely see the ground through the mulch before it is crimped. 

-Wes Gibbs, Jones County, 2024

To apply straw mulch, I use a small bale blower with a gas motor. It does a nice job of shredding up the bales. The process is labor intensive and, so I usually only tackle small projects with it. The big round bale blowers/shredders (I don’t have one) are less labor intensive and can cover a lot more area in less time.  This method requires mobilization for the bales and a large tractor to run it .  I generally mulch at 1000 to 1500 lbs. per acre. 

-Ben Hoskinson, Mahaska County, 2011

Our mulch tucker / cultipacker combo is 8 ft. wide and weighs 1600 lbs. We pull it with a 95 HP tractor – you might be able to go a little smaller as long as you have sufficient weight in front to balance it when in the “up” position. 

-Wes Gibbs, Jones County, 2024

We always use 1.5 tons/acre of straw mulch.

-Ole Skaar, Roadside Development, Iowa DOT, 2011

We have a couple organic farmers in the county. When I need straw, I buy it from them. They usually have a field in their rotational plan that will be in oats. I support the concept and like to help them in this small way.

-Linn Reece, Hardin County, 2011

If harvested in the fall just after the seed heads have matured, prairie hay bales will carry enough seed to plant a new site. Some seed supplement may need to be used. I think prairie hay works better than straw. It is just reedy enough that it lays out and kind of locks together.  Straw is a lot lighter and doesn’t lay down as well. 

-Ben Hoskinson, Mahaska County, 2011


Hydromulch

Hydromulches are applied with or on top of seed to conserve soil moisture and, depending on type, prevent splash, sheet or rill erosion.  None are suitable to withstand the shear stress of concentrated-flow situations.

Common types of hydromulch

Cellulose (paper)

Made from recycled newspaper, magazines and corrugated cardboard, cellulose is the least expensive hydromulch. Its advantages over wood fiber mulch include: greater water retention, quicker mixing and better pumpability. Cellulose may be the least effective at controlling erosion since it does not have long, interlocking fibers. Be aware of the “paper mache” effect which reduces moisture and airflow to seed, and occurs when cellulose is applied too heavily or with too much tackifier.

Wood fiber

Wood fiber mulch is produced from milled wood, typically aspen. It is more expensive than cellulose and does not hold as much moisture, but it has more loft and the interlocking fibers provide greater erosion control.

Wood/cellulose blend

Blended  mulch usually consists of 50-70% wood fiber and 30-50% paper products. It falls in the middle of the two previous mulches in terms of cost, water retention, pumpability and erosion protection.

BFM (bonded fiber matrix)

BFM is a wood fiber mulch — usually with elongated fibers — containing various adhesives, binders and synthetic fibers. BFM mulches retain their strength much longer than traditional mulches.

MBFM (mechanically bonded fiber matrix) and FGM (flexible growth media)

These mulches contain elongated wood fibers and crimped synthetic fibers along with various adhesives and binders. The crimped fibers provide a strong, mechanical, fiber-fiber-soil bond. No cure time is required to provide erosion protection.

Hydromulch application

Hydromulch is mixed with water and often a tackifier in a truck- or trailer-mounted tank. Spraying the slurry on to the site is called “hydromulching.” When “hydroseeding,” seed and amendments are added to the slurry. The terms are often used interchangeably. Recommended hydromulching rates are shown in Table 1 and discussed in "Seeding Methods."

Tackifiers bind mulch fibers to each other and to the soil, enhancing erosion protection. Tackifiers can be purchased separately or be pre-blended in the mulch. Organic and synthetic tackifiers are available. All products have different recommended rates. See manufacturer recommendations before application.

Tackifying agents are preblended in BFM, MBFM and FGM products and undergo a chemical process known as “cross-linking” which prevents rainfall from rewetting and dissolving the tackifier after it is applied.

Amendments are added to the slurry to accelerate seed germination and establishment and improve poor soils. Amendments include water soluble fertilizer, water-storing polymers and plant growth stimulants. Refer to the manufacturer for recommended rates. Peat moss and compost screenings can also be added as a soil amendment, though little research exists on rates.

Synthetic fibers can be added as an amendment to increase the mechanical bond of traditional wood fiber and blended mulches.

Hydromulch profile
A chart showing five common types of hydromulch that can be used at increasing slope angles and slope lengths.
Courtesy of landandwater.com.

Roadside manager insights

An important factor that can get overlooked when dealing with sheet erosion is the additional overland flow that may be coming from the roadway. This can really affect hydroseeded areas, and increased rates of hydromulch may be needed. This doesn’t seem to be an issue when using blankets – which makes sense since blankets are appropriate for protection against channelized flow.

-Jim Uthe/James Devig, Dallas County, 2024

SUDAS section 7E-5 deals with mulching to prevent sheet erosion, but I feel they are overly cautious. For instance they don’t recommend hydromulching on slopes steeper than 6:1. I recommend looking at manufacturer specs for available products.

-Jim Uthe, James Devig, Dallas County, 2024

I use a wood/paper blend which I think works the best. The wood I’ve used by itself doesn’t have enough substance. I also use FGMs or BFMs as a supplement to the wood/paper or as a stand alone.

-Ben Hoskinson, Mahaska County, 2011


Compost blanket

Typically used on poor soil, a compost blanket is a 1–4 inch layer of compost applied with a blower truck. The compost is a blend of coarse and fine material. If seed is applied with the blanket, the layer should not exceed 2 inches; establishing roots may not penetrate the underlying soil if the blanket is deeper. Be sure the compost is well-cured; if applied while still “hot,” vegetation may not establish.

A compost blanket should not be used where overland flow is expected. The blanket will absorb rainfall, but overland flow can erode the compost. If the blanket must be used in areas with overland flow, till in the compost.

When applied correctly, compost blankets are very effective at preventing erosion and promoting seed growth. Specialized equipment is necessary to properly apply compost blankets, so a contractor is typically hired. Due to the expense, a guarantee should be requested to ensure the job is done correctly.

Rolled erosion control products (RECPs)

RECPs are arguably the best way to stabilize most channel areas. They are also used to stabilize slopes. Because RECPs need vegetation to function properly, site conditions must be conducive to vegetation establishment. In extremely poor soils or deep shade, riprap or erosion stone may be the best option. Temporary and permanent rolled products are available.

Manufacturers of RECPs provide specs for their products online. Most manufacturers also provide software to help determine the appropriate product for a given site. A list of virtually all RECPs on the market and their specifications is in the Geosynthetics Specifier’s Guide.

Types of RECPs

Erosion control blankets (ECBs)

Erosion control blankets are temporary, degradable rolled products made of natural or polymer fibers mechanically, structurally or chemically bound together to form a continuous matrix. Blankets are usually classified as netlesssingle-net or double-net.

Netless blankets consist of fibers stitched together with a biodegradable thread. Because there is no net, this product is typically used in intensively mowed areas and areas where animals could become entangled in netted products.

Single- and double-net blankets consist of one or two polymer or jute nettings interwoven with natural fibers — typically straw, coir (coconut) and/or excelsior. In general, netless and single-net are used on slopes or in low-flow channels. Double-net can be used on slopes and in higher-flow channels.

Turf reinforcement mat (TRMs)

TRMs are permanentnon-degradable, rolled products made of synthetic materials. These three-dimensional mats provide immediate erosion protection, enhance vegetation establishment and offer long-term functionality by permanently reinforcing vegetation. TRMs are typically used in high-flow ditch channels and on very steep slopes where unreinforced vegetation may not provide adequate erosion protection.

SUDAS classifies TRMs by material and by their performance in channel and slope applications. Refer to Table 1 for more information.

Selecting the appropriate RECP

Slope applications

Manufacturers’ general application guidelines are the easiest way to select a product. A link to an example of these guidelines is provided here. Slope length and grade are used as criteria. Product longevity (determined primarily by material weight) must also be considered when using degradable products. Time of year, soil fertility, aspect, seed mix and other factors affect how quickly vegetation establishes. A product may be appropriate for a specific slope length and grade, but if installed over a seeding in poor soil, it may deteriorate before vegetation establishment.

Manufacturer software is also used to select products for slope protection. Links to examples are provided below. Slope length and grade, surface condition of the soil and the soil erodibility (K) factor for the soil type (found in the NRCS soil survey for each county) are entered in the program which then suggests multiple appropriate products. Growing conditions and seed mixes determine the appropriate functional longevity.

Software examples

Channel applications

When stabilizing a concentrated flow area with temporary RECPs, estimate the amount of flow and time it will take for vegetation to establish. Then use manufacturer specs to select a blanket with the appropriate strength and longevity.

For large-scale projects, especially in high-flow situations, further analysis may be necessary:

  1. Determine channel dimensions, including width and grade of the channel bed and slopes of each side of the channel.
  2. Determine the amount of flow, in cubic feet per second (CFS). Flow determination for a given rain event can be done with complex mathematical formulas (performed by engineering staff) or by observing the channel’s watershed and making an educated guess. When protecting channels at culvert outlets, design protection to withstand maximum discharge.
  3. Consider the consequences of failure to decide whether the project requires protection against a two-year storm, five-year storm, ten-year storm, etc. According to CPESC (Certified Professional in Erosion and Sediment Control) guidelines, when using permanent RECPs (TRMs), projects are usually designed to withstand the ten-year frequency, 24-hour duration rainfall event. This is about 4 inches in northern Iowa and 5 inches in the southern part of the state.
  1. Enter channel dimensions and flow into the manufacturer’s software, available at their website, to determine an appropriate blanket.
A chart showing categories of hydraulic mulch in order of increasing performance.
Courtesy of landandwater.com.

Installing RECPs

Erosion control blanket installation

  • Provide good blanket-to-soil contact by creating a smooth soil surface.
  • Trench the top of the blanket to a depth of 6 in. and staple at the bottom of the trench.
  • Any blanket overlap should be at least 6 in.
  • Refer to the manufacturer’s specs for recommended stapling patterns. In the absence of instructions, staple in a staggered pattern using 3-ft. centers on a slope and 2-ft. centers on a channel.
  • In channel applications, center a blanket in the channel bottom to avoid having a seam under the area of maximum flow. At 25-33 ft. intervals, place a check strip of staples 2-4 in. apart across the blanket.
  • Install additional staples in uneven ground to ensure good soil contact especially in low points.

RECPs are often maintenance-free after vegetation has established. Until then, inspect after every runoff event, adding staples where erosion has occurred. Routine maintenance is easier than repairing and reseeding the large ruts and gullies that can form under improperly installed or maintained RECPs.

TRM installation

  • When used in areas saturated for long durations, provide subsurface drainage to prevent erosion under the mat.
  • Anchor mats with 6 in. staples. Use 8 in. staples or stakes in high-flow and loose-soil situations. 
  • For slope stabilizations, anchor mats with high performance duckbill anchors or ScourStop anchors.
  • Seed should be drilled or hydroseeded (not broadcast) to prevent small seed from floating up through holes in the mat and washing away during high-flow events.
  • In high-flow situations, BFMs can be used under the mat. Laying sod underneath will provide instant erosion control.
  • In slope stabilizations, soil can be placed over the mats. In concentrated flow areas, the top layer of soil will wash away unless straw or excelsior blanket is placed on top.
  • TRMs can be infilled with BFMs and FGMs in both channel and slope applications.

Roadside manager insights

I had heard at one time that forbs germinate better under straw than excelsior, but I’m starting to become a skeptic on that claim. For instance, I just inspected a project where we used Curlex-2 and there were just as many partridge pea seedlings in the blanketed areas.

-Jim Uthe, James Devig, Dallas County, 2024

TRMS can stabilize very steep slopes, but in a typical county roadside setting it may be cheaper to buy more right-of-way, grade it to a generally slope, and stabilize by hydroseeding or seeding/mulching.

-Jim Uthe, James Devig, Dallas County, 2024

We used double-net, straw/coconut blankets for concentrated flow areas with success, but due to the cost we’re switching to double-net straw. They seem to allow just as good germination as the straw/coconut blend and are almost $20 cheaper per 100 ft. roll. They seem to provide adequate protection in a typical ditch bottom, but don’t last as long.

Single-net straw blankets are available, but they only work in low-flow channels and are much more difficult to unroll than double-net. Double-nets are only about $7-10 more.

-Jim Uthe, James Devig, Dallas County, 2024

If you’re doing a lot of RECP installations, get a staple gun. It’s worth the money! And if you need to cover a lot of surface area, I suggest the 16 ft. rolls (vs. the more common 8 ft. rolls). They’re still fairly easy to handle and they cut your installation time and labor almost in half. 

-Wes Gibbs, Jones County, 2024

We do not use straw or straw/coir blankets in channels. Those materials don’t absorb water like excelsior, so the blankets float if rain causes any flow. You might get them to work with sediment logs or lots of staples, but that isn’t cost effective. Nothing beats good wood excelsior.

-Ole Skaar, Roadside Development, Iowa DOT, 2011


Other

Flow transition mats

Flow transition mats are a “green” alternative for riprap or concrete in the transition area between flow outlets and channel flow. The semi-rigid, plastic mats – approximately 4 ft. x 4 ft. x ½ in. – are designed with holes which allow vegetation to grow. The mats are installed on top of a TRM in areas of high scour, such as culvert outlets. Flow transition mats can provide better protection than riprap and installation is an easy, one-man job.

  • When placing transition mats over fill, make sure area is well-compacted to prevent failure from settling.
  • Use subsurface drainage in areas with long durations of saturation.
  • For best results, place sod underneath the TRM.
  • If not using sod, high-flow events can cause erosion before vegetation establishes. To help minimize erosion, install a staple check strip in the TRM directly downstream of the transition mat.
  • Check mats after every runoff event during the first two seasons to make sure anchors are still tight.

Roadside manager insights

ScourStop can be used as a riprap alternative for channel protection if flow occurs only during larger rain events. The channel needs to dry out at times so vegetation can establish.

-Ole Skaar, Roadside Development, Iowa DOT, 2011

Sediment Control

Sediment Control thompsbb

Containing eroded soil on the project site will be the responsibility of some IRVM programs. Basic sediment control products likely to be used on county rights-of-way are described below.

Wattles, sediment logs and filter socks

Wattles and sediment logs are tubes of straw, coir or excelsior fibers encased in burlap or degradable plastic netting and anchored by wooden stakes. Both filter sediment and slow water flow. Wattles and logs containing densely packed material – especially straw – are good as slope interrupters. Excelsior logs are more porous and less likely to float, so are better suited for ditch checks. Both are good for perimeter applications and inlet protection.

Filter socks are degradable tubes filled with compost, generally used for perimeter control or at intervals along a slope to capture sheet flow. To enhance sediment control, polyacrylamide (PAM) may be added to the compost. PAM captures clay particles creating cleaner runoff.

Wattles, logs and filter socks are usually easy to install and can be put on bare soil or over erosion control blankets.

Silt fence

Silt fences are geotextile barriers trenched in to the ground and supported by posts. They are useful on perimeters and in channels with relatively low flow. Silt fences filter out small amounts of sediment as runoff passes through the fabric. They need to be kept clean to function properly and must be removed after final stabilization, but are easy to install and relatively low cost.

Silt fences are not effective in high-volume flows and should not be used as a check dam. During moderate or heavy rains, a silt fence check dam will concentrate water from the entire channel, along with the water’s energy. This concentration either goes around the outside of the fence or over the top at the lowest point. It can also go underneath the fence, causing erosion.

Silt fences are ineffective when improperly installed, and improper installation is common. To avoid the problems inherent with these practices, follow up-to-date specifications such as those found here:

Check dams

Check dams should be constructed of clean rock, permeable plastic berms or similar products. Unlike silt fence, check dams do not cause water to dam up; they let water pass through – slowing its velocity and dissipating its energy.

Sedimentation can occur on the upstream side. If it becomes too great the check dam will function as a waterfall and the project may begin to fail. Monitor and excavate the upstream side if necessary.

Plastic berms should not be placed in areas susceptible to filling with debris (e.g., corn stubble from a field waterway).  One heavy rain can cause these berms to fill with stubble, creating a dam.

Improper check dam design is not uncommon and can cause project failure.  Follow current design specs, and account for the individual characteristics of each site.


Roadside manager insights

If a rain event is relatively small, silt fences will function properly. But small rain events typically cause little to no erosion. Silt fences may be good for PR but they create a point of failure for the project. A roadside is essentially a headwater stream. Stream dynamics show that flow = area*velocity. When the water from a flat, six-foot wide channel is concentrated into a width of typically less than a foot at the low point of a silt fence, the water’s velocity increases substantially, thus erosion is caused instead of prevented.

-Jim Uthe, James Devig, Dallas County, 2024

Rock checks should mostly be below ground. The “waterfall” problems can be eliminated if the check doesn’t extend above ground-level.

-Wes Gibbs, Jones County, 2024


Erosion and sediment control web sites

Weed Control

Weed Control thompsbb
A sign reading "Roadside prairie restoration, no spraying or mowing" among greed roadside vegetation.

Iowa Code section 317.11 states: The county boards of supervisors and the state department of transportation shall control noxious weeds growing on the roads under their jurisdiction. Spraying for control of noxious weeds shall be limited to those circumstances when it is not practical to mow or otherwise control the noxious weeds.

Objective

Objective thompsbb

Develop a county weed control program that provides:

  • Responsible weed control
  • Wise use of taxpayer dollars

Groundwater and surface water protection

An integrated approach to roadside vegetation management means relying on a variety of weed control methods: mechanical, biological, chemical and cultural. IRVM emphasizes cultural control — establishing and promoting healthy, native vegetation – and tries not to rely exclusively on herbicides for controlling weeds.

Establish native vegetation

Native vegetation is the cornerstone of IRVM. Plant the best-adapted vegetation and keep it healthy. Iowa native plants are naturally adapted to the state’s climate and growing conditions. They handle tough roadside conditions. Their tall growth and deep roots help prevent weeds. Keep the natives healthy with the use of prescribed fire.

Do not overuse herbicides

Overuse of herbicides weakens all vegetation, making roadsides more susceptible to invasion by weeds. Overuse of herbicides also eliminates desirable and harmless broadleaf species that would otherwise reduce weed invasion by occupying the same niche sought by weeds. For these reasons IRVM promotes careful spot-treatment of weeds when using herbicides.

Consider mowing

Mowing must be considered before resorting to herbicides. The effectiveness of mowing depends on target species and timing. The feasibility of mowing depends on roadside slope and available equipment. County road right-of-way is often not suited to tractors. Still, spot-mowing for weed control is encouraged and counties should look for ways to make this a more frequent and viable weed control option.

Pay attention to timing

Timing is key to successful vegetation management; the effectiveness of mowing and spraying depends on it. IRVM recommends hiring a full-time roadside manager as the best way to provide professional, proactive and systemic weed control.

Keep goals realistic

IRVM recognizes there is no such thing as total weed eradication, so have realistic goals. Accept the presence of some weeds and keep them at a manageable level. Weed species that post no real threat to agriculture or natural areas should be tolerated. Prioritize weed control efforts, beginning with highly traveled roads.

Weed Life Cycles and Control Strategies

Weed Life Cycles and Control Strategies thompsbb

Annual weeds 

Annual weeds have a one-year life cycle. They germinate, grow, flower, set seed and die in one year or less. They reproduce by seed only. Common roadside annuals include common ragweed and giant ragweed.

To control:

  • Mow prior to seed-set.
  • Eliminate bare soil and disturbances to vegetation.

Biennial weeds 

Biennial weeds have a two-year life cycle. In the first year a basal rosette (circular cluster of leaves on or near the ground) is produced. The second year a central flowering stalk elongates and the plant dies after seed maturation. Biennials spread only by seed. Common roadside biennials include musk thistle, bull thistle, poison hemlock, wild parsnip and wild carrot.

To control:

  • Mow prior to seed-set five consecutive years.
  • Treat rosette plants with herbicides in fall or early spring when results are typically the best and damage to desirable plants can be minimized. (Biennials become much more tolerant of herbicides after the stem has elongated.)
  • Establish native vegetation to deprive biennials of sunlight during their weak seedling stage.

Perennial weeds

Perennial weeds can live for a few years or for many years. Some perennials reproduce only by seed; many spread by seed and a variety of underground reproductive structures. Control of these perennials may be very difficult because of their extensive root systems.

To control:

  • Treat with herbicides.
  • Mow to prevent seed maturation and extend the herbicide treatment window.
  • Establish a diverse, native plant community.

Iowa's Herbaceous Roadside Vegetation Threats

Iowa's Herbaceous Roadside Vegetation Threats thompsbb

Iowa’s noxious weed list is outdated. It includes several species that no longer pose a threat to agriculture, and it does not include certain plant species now considered troublesome in the state.

The state’s primary herbaceous (non-woody) roadside threats are listed in Table 2. Herbicides remain the most practical means of controlling these weeds in county road right-of-way.

Table 2: Iowa's Primary Roadside Threats and Herbicide Recommendations

Species

Roadside Manager Recommendations (2011)

Application Schedule and Notes
(refer to product lable for recommended rates)

Canada Thistle
perennial
  • Milestone
  • Transline (early season)
  • Telar (late season)
  • Transline/Telar (mid-season)
  • Perspective

Most effective control: Bud to bloom, or late fall just before frost; mowing increases efficacy of fall treatments. Growth stage is key, so treatment can be flexible:

  • We've had success killing thistles with Milestone in early-August if they were mowed in June/July and have adequate regrowth.
  • We've also had good luck with Milestone after hard frosts, as late as the last week in October. As long as it's green in the fall, spray it! Volatility may be an issue with Perspective in the summer.
Musk Thistle
biennial
  • Milestone
  • Opensight
  • Escort XP
  • Transline
  • Garlon
  • Streamline
  • Overdrive
  • 2, 4-D

Most effective control: Rosette stage during spring or fall.

Herbicides with good residual activity (e.g., Milestone, Opensight) appear to be the most effective over the long-term.

Adding 2, 4-D helps with burndown. Tank mixing, 2, 4-D, with Overdrive = very rapid burndown.

Bull Thistle
biennial
  • Milestone
  • Opensight
  • Escort XP
  • Transline
  • Garlon
  • Perspective
  • 2, 4-D
Same as musk thistle
Teasel
biennial
  • Milestone
  • Escort XP
  • Garlon
  • Roundup
  • Transline
  • 2, 4-D

Most effective control: Rosette stage during spring or fall.

For small populations, cut off seedheads, destroy and dispose properly.

Use a stout dose of herbicide and monitor. Teasel is tough; flowerheads and seed can be produced after treatment.

Poison Hemlock
biennial
  • Opensight
  • Telar
  • Roundup
  • 2, 4-D
Most effective control: Rosette through pre-bloom, early spring.
Leafy Spurge
perennial
  • Plateau
  • Banvel
  • Vanquish
  • Perspective
  • Roundup/2, 4-D

Most effective control: Spring or fall. Plateau works well and is most effective in the fall, just before frost.

Pull or respray plants that appear after treatment.

Use biocontrol for large infestations: flea beetles (Aphthona spp.).

Purple Loosestrife
perennial
  • Garlon 3A
  • Aquatic Roundup
  • Habitat
Most effective control: June to August.
Wild Parsnip
biennial
  • Escort
  • Opensight
  • 2, 4-D
Most effective control: Rosette stage.
Japanese Knotweed 
perennial
  • Habitat
  • Polaris
  • Arsenal Powerline
  • Roundup

Most effective control: Summer

Use a good surfactant, e.g., MSO with Arsenal, and Liberate with Habitat.

Sericea Lespedeza
perennial
  • Garlon
  • Escort XP
Can use either herbicide all summer. For best results use Garlon prior to branching (~July 4), and Escort in Aug. & Sept.
Russian Knapweed
perennial
  • Milestone
  • Perspective
Most effective control: Spring.
Garlic Mustard
biennial
  • Roundup
Spray rosettes in early spring (late Feb - early April) or late fall when little else is green to avoid non-target plants. Escort XP and Streamline may be effective, but due to residual activity should not be used where non-target species could be affected.

Notes: The most commonly used brand names are shown here. Many of these products are now available under other (often less-expensive) labels.

Where Garlon (triclopyr) is noted, either Garlon 3A (amine formulation) or Garlon 4 (ester) can be used. Garlon 4 is usually more effective but in hot weather can volatilize, drift and affect non-target species. 3A is non-volatile and usually considered the best choice for hot weather.

Herbicide labels

Labels explain how to use the product effectively while protecting yourself, non-target plants and the environment. Take time to read the labels; it may be the most valuable time spent in weed control.

Adjuvants

Adjuvants are often added to the herbicide solution to increase its effectiveness. These products are put in the water tank at labeled rates.

  • Surfactants improve dispersion and reduce surface tension of spray droplets resulting in increased penetration. 
  • Crop oils and crop oil concentrates also improve dispersion and, by being oil, keep leaf surfaces moist longer than water allowing more time for penetration.
  • Stickers help prevent the solution from being washed off leaves.
  • Drift inhibitors control drift.
  • Antifoaming agents reduce foaming in the tank so it can be filled more easily.

Iowa's Roadside Trees and Brush

Iowa's Roadside Trees and Brush thompsbb

Iowa’s noxious weed list includes a few woody species and several non-listed trees and shrubs have become troublesome in non-agricultural land throughout the state. In roadsides, all trees and brush are potential safety hazards. The primary goal of county roadside tree and brush control is to provide safe roads for the traveling public. Safety goals include:

  • Provide motorists unobstructed lines of sight.
  • Ensure visibility of traffic control and warning signs.
  • Eliminate immovable objects.
  • Alleviate substantial and chronic drifting of snow.
  • Reduce shade where it prolongs ice on the road.

Most roadside tree and brush control is accomplished by mechanical or chemical means. A correctly timed prescribed burn can also control brush.

Refer to "Tree and Brush Control for County Road Right-of-Way," a 2002 Iowa Highway Research Board/UNI-IRVM publication, for complete brush control information. Herbicide recommendations from that publication — with updates  — are shown in the appendix.

Ways to Reduce Herbicide Use

Ways to Reduce Herbicide Use thompsbb
  • Know which weeds (under what circumstances) actually constitute threats.
  • Know each herbicide’s target species and appropriate application schedule.
  • Know the latest, most accurate herbicide application technology.
  • Work with adjacent landowners to eliminate disturbances that cause weeds.
  • Hire conservation-minded operators for county spray crews.
  • Resists outside pressure to do more spraying.

Landowner Education

Landowner Education thompsbb

Resisting outside pressure to apply more chemicals might require educating a landowner — or even a member of the board of supervisors — why it might be inappropriate to spray. The following points can be helpful when talking to someone whose weed control philosophy is based primarily on experience with row crops and lawns.

  • Roadside weed control bears no resemblance to row-crop weed control. Corn and soybeans are annual species maintained in bare soil, a practice that invites weeds and requires continual cultivation and herbicide use. Native seed mixes designed for roadsides create diverse stands of perennial vegetation that prevent weeds by occupying all available space. Overuse of herbicides works against this method of weed control.
  • Native prairie grasses and wildflowers may be tall and can appear unkempt, but these are the plant species most adapted to Iowa’s climate and growing conditions. Their extremely deep roots enable them to survive environmental stresses and their  unique metabolism allows them to grow tall and thrive during long, hot summers. Because of these characteristics, native plants outcompete weeds.
  • Broadleaf species (wildflowers) included in native seed mixes are part of the plan. They occupy a niche in the plant community otherwise used by weeds. They are not a threat to agriculture.
  • A pure stand of any grass is an unnatural condition sustainable only through the use of herbicide.
  • Overuse of herbicides in any roadside creates openings for weeds by weakening grasses and eliminating beneficial broadleaf species.

County Weed Control

County Weed Control thompsbb

Most counties that provide their own weed control:

  • Dedicate one full-time employee for much of the summer
  • Hire two seasonal employees
  • Purchase and maintain one primary spray rig
  • Spend between $8,000 and $24,000 on chemicals each year
  • Cover at least half the county each year
  • Maintain herbicide applicator licenses and certifications
  • Provide proper herbicide storage
  • Properly dispose of herbicide containers
  • Keep up with the latest developments in herbicide and sprayer technology

Benefits of providing in-house county weed control:

  • The county has more control over how roadsides are managed. Sensitive areas such as gardens, bee hives, organic farms, prairie remnants and roadside wildflowers are protected.
  • Having someone on staff who knows how to apply herbicides and effectively control weeds is a great asset for roadside management and management of county recreation areas as well.
  • When the person overseeing the program lives in the county, personal pride and accountability become part of the equation, resulting in a more conscientious effort.

IRVM Herbicide Application History

IRVM Herbicide Application History thompsbb

In the early days of IRVM, many counties sent crews into the ditch equipped with backpack sprayers. They carefully spot-sprayed weeds. While this method provided good weed control with a minimal amount of herbicide, roadside managers soon learned they could not cover enough of the county.

Since then IRVM has helped drive the development of spray truck technology that delivers herbicides with the accuracy and control needed to live up to the program’s original principles — killing target species without weakening non-target species or putting too much chemical on the ground.

Progress has been made, not just with more responsive on/off control switches and multi-directional spray nozzles, but with systems that monitor flow, record data and greatly reduce operator exposure. As with any spray equipment, these systems are only as good as the person whose finger is on the trigger. The objective is still to spot-spray. Beware of getting comfortable and sitting too long in the cab. Be conscientious, stay alert and be ready to grab the handheld sprayer and walk to that distant shrub to treat it properly. Never underestimate the value of your own labor; sometimes it’s still best to put on the old backpack.


Roadside manager insights

We don’t spray shoulders, just bridge abutments and guardrails.

-Jim Uthe, James Devig, Dallas County, 2024

We don’t spray wild parsnip unless asked or if there’s a really rank patch. Unfortunately, if we tried to spray every parsnip plant we’d essentially be blanket spraying many areas. 

-Jim Uthe, James Devig, Dallas County, 2024

I publicize in the paper when we will start spraying, and encourage people to call me with locations of sensitive areas – gardens, bee hives, allergies, etc. I have “No Spray Zone” signs for willing landowners. 

-Jeff Chase, Des Moines County, 2024

Higher diversity roadsides are more robust, more resistant to weeds. Maintain high diversity even if you don’t have the opportunity to establish natives. Don’t spray species that are not creating problems.

-Wes Gibbs, Jones County, 2024

Our goal each season is to cover half the county for noxious weeds and the other half for brush. Most of the weed spraying is noxious thistles and teasel. When spraying brush, we try to cover areas in which brush and trees were cut the prior winter to catch any re-growth.  

-Wes Gibbs, Jones County, 2024

We have isolated patches of garlic mustard that get sprayed. However, what exists in the ditch is usually spill over from the woods. What makes it to the ROW is just the tip of the iceberg, so I don’t get too excited about chasing it down. We have plenty of parsnip that, historically, was sprayed every year. Still have plenty of it. We currently do not spray parsnip. 

-Wes Gibbs, Jones County, 2024

I mostly use the web or my sales rep for technical support. It’s too hard to maintain up-to-date, written information on the most effective herbicides for each species. But like anything else, the advice is only as good as the source.

-Josh Brandt, Cerro Gordo County, 2009

Spray Systems

Spray Systems thompsbb

Counties typically used truck- or trailer-mounted chemical injection (high-end) or tank mix (basic) spray systems. The following is one county’s description of its two spray rigs. These fairly well represent the range of equipment available.

Our high-end unit is a Legacy 6000 chemical injection system from Mid Tech. This unit has a GPS to record the rate, type and amount of chemical used. We download that info to our desktop and print our reports. Our system has three injection pumps with three chemical tanks, and a 300-gallon water tank all on a skid for easy loading and unloading on the pickup. All the controls and the electric start are mounted in the cab on a computer stand. We have three bumper-mounted spray nozzles — 6 ft., 20 ft. and 30 ft. — and a hose reel with 300 ft. of hose in the back. We like this unit because we can easily switch chemicals to spray something else and one person can load and unload everything in less than an hour. A downside of this system — we can only use liquid chemicals, otherwise everything gets plugged up.

Our basic unit can also be loaded in the truck by one person. Just about any chemical can be used because it’s a tank mix system with an agitator in the tank. It has a 200-gallon tank, also on a skid, run by a 5 ½ HP motor. We have two nozzles, a 6 ft. and a 30 ft. on the right-front bumper. There is a hose reel in the back with 200 ft. of hose. There’s no GPS on this system, so we have to keep track of everything. We mounted switches in the cab to run the nozzles, but we have to get out to turn the system on and off.

Another type of truck-mounted spray system used in roadsides is an invert emulsion sprayer. Invert emulsion was developed to reduce herbicide drift and volatilization by producing large droplets of water surrounded by oil. The mayonnaise-textured droplets do not dry as fast as water, so leaf penetration is improved. Invert emulsion sprayers do not work with all types of chemical products; liquid formulations usually work best.

Spray Nozzles

Spray Nozzles thompsbb

Bumper=mounted nozzles or raised, multi-section, nutating spray nozzles are typically used on county rigs. The following is one county’s description of both nozzle types:

A multi-section, nutating spray head allows a mindful operator to choose which section of the ditch to spray — in 2, 4 or 6 foot increments out to 30 feet. A system with multiple bumper-mounted nozzles can spray different distances too, but they tend to spray everything up to that distance. The mutli-section system uses less herbicide primarily by hitting a narrower band. But if operators of multi-section systems hit all seven switches every time they spray a single thistle — just to make sure they don’t miss — there won’t be much reduction in herbicide. Ultimately a good operator still makes the difference.

Spray System Components With Option

Spray System Components With Option thompsbb
  • Skid-mounted or permanent truck or trailer installation 
  • Water tank: typically 300–750 gal; 1,000-gal requires CDL
  • Chemical mixing systems: tank-mix system with mechanical agitation (chemicals added manually to the large water tank) or chemical injection system with 2 to 3 separate chemical tanks (chemicals mixed with water after passing from tank)
  • Water pump: roller, piston, centrifugal and diaphragm pumps are used
  • Water pump motor: 5.5–11 HP; Honda is popular
  • Injection pumps: at least 20 to 40 GPM; elect
  • Hose reel: 200 to 300 ft.; ½ in. to ¾ in.; electric rewind recommended
  • Spray gun or spray wand attached to hose
  • Truck-mounted spray heads; one side; generally either 2 to 4 bumper-mounted nozzles or a raised, nutating head with multi-direction spray sections
  • Console: holds controllers, switches, GPS, computer
  • Controller: sets application rate
  • Flow meter: records herbicide application data
  • GPS: maps spray location
  • Software

Backpack Sprayers

Backpack Sprayers thompsbb

The backpack sprayer is the best way to reduce herbicide use and target specific invasive plants, especially in diverse wildflower plantings.

  • Use a low-volume backpack sprayer. BirchmeierTM and SoloTM are good brands.
  • A 4-ft. wand reaches right down to the target plant.
  • Herbicides made to kill broadleaf weeds will also kill wildflowers.
  • Transline works on tough weeds without a lot of residual effect.
  • Follow the rates on the label for mixing the spray.

Pesticide Applicator Certification

Pesticide Applicator Certification thompsbb

Anyone who applies pesticides for a county agency or other government entity must be certified. The Iowa Department of Agriculture and Land Stewardship-Pesticide Bureau administers the state’s pesticide applicator certification process. A description of this process — and related information — are in the appendix.


Roadside manager insights

We have an 800 gal tank. I like using a lot of water; bigger droplets = less drift.

-Jim Uthe, James Devig, Dallas County, 2024

Our spray rig came with an 8HP engine which failed due to a mechanic’s error and was replaced with an 11HP due to availability. It lasted 8 or 9 years and was replaced with a 13HP which lasted 8 or 9 years too. We are on our second 13HP now. Our pump is a Hypro centrifugal pump with an electric clutch.

-Jim Uthe, James Devig, Dallas County, 2024

The Legacy 6000 can be used as a datalogger and rate controller. When our old datalogger died, we just piggybacked the Legacy onto our existing rate controller because it was a lot less work than redoing everything.

-Jim Uthe, James Devig, Dallas County, 2024

We recommended a minimum of 2 chemical injection tanks, 1 brush, 1 thistle. We used to put 2,4-D in our third tank for use on large patches of various undesirable weeds (giant ragweed, hemp, crown vetch, parsnip, hemlock, etc.). Now we put a low rate (5 oz/ac) of Method herbicide in the third tank and use it in addition to our brush mix when spraying honeysuckle.  

-Jim Uthe, James Devig, Dallas County, 2024

Internet Resources

Internet Resources thompsbb

Excellent, up-to-date information about invasive species and their control is available on the web. Take advantage of the following websites.

Weed and invasive species information

  • Invasive Plants webpage from the University of Wisconsin-Madison. Good general invasive plant management information and fact sheets from the University of Wisconsin's Integrated Pest and Crop Management program.
  • Invasive Plant Atlas of the United States. Many of Iowa's invasive/nuisance plants are included in this list of invasive species of the Eastern United States. Pictures and control methods are provided. 

Herbicide information

Herbicide Resources

Herbicide Resources thompsbb

Herbicide suppliers

  • Midwest Spray Team & Sales, Inc., Lyle Christensen, 515-238-1616
  • Chem-Trol Vegetation Management Supply, Dave Suther, 515-223-0202
  • Van Diest Supply, Chris Roberts, 515-314-3898

Herbicide manufacturers & reps

  • Dow AgroSciences
  • DuPont Land Management
  • Nutrient Solutions.‌

Herbicide spray equipment companies

  • C&R Supply
  • Chem-Trol Vegetation Management Supply
  • Dultmeier Sales
  • Minnesota Wanner

Prescribed Burning

Prescribed Burning thompsbb
Flames of a prescribed prairie burn around the outside of a field of prairie grass.

Prescribed fire is an essential component of native vegetation establishment and management. Though challenges are associated with the process, prescribed burning can be executed safely and effectively in the roadside environment.

Prescribed fire is a management tool used for two main objectives:

  • Discourage the growth of invasive and woody plants.
  • Invigorate the growth of native plants.

A timely burn can slow the growth and spread of weeds and small trees, both of which are susceptible to the intense heat associated with fire. Most native prairie species, on the other hand, have a positive response to fire. Historically, this ecological relationship was critical to the existence of the tallgrass prairie, and today it continues to be an essential management practice in roadside prairie remnants and plantings.

Preparing for a Burn Season

Preparing for a Burn Season thompsbb

Property trained staff, the right equipment and advance planning are key to a successful and safe prescribed burn.

Training and personnel requirements

Though there are no state-wide minimum requirements for individuals participating in roadside burns, training opportunities are administered by the Iowa DNR that provide basic information for performing safe prescribed burns.

The minimum recommended training session is S130/190, which covers the basics of fire behavior and wildfire fighting techniques. This 40-hour course, combined with an annual eight-hour refresher, is adequate preparation to participate in a prescribed roadside burn. A combination of experience and additional training may be necessary to plan and lead a successful and safe burn.

Staff requirements for roadside burns vary with the conditions at each site; the size of the crew depends on the size and complexity of the burn. As a general rule, two to four qualified people can safely execute most roadside burns. Burning alone or understaffed is not advised, so it may be necessary to coordinate efforts with other agencies. Secondary road maintenance crews, county conservation boards, local fire departments, and other county IRVM programs are possible partners.

Personal Protective Equipment (PPE) standards vary among agencies, but some general guidelines should be considered.

Minimum suggested PPE

  • Leather work boots
  • Gloves
  • Safety glasses
  • Clothing made of natural fibers

Roadside manager insights

Burning in the ROW can be dangerous, try to minimize smoke over the road and set up work zone flagging if necessary. 

-Joe Kooiker, Story County 2024

Prescribed Fire in the ROW can be difficult but is an important part of the roadside program. Roadside burning is a great tool and should be utilized. 

-Joe Kooiker, Story County 2024

Plan for the worst with water and equipment so you’re not under-prepared. Roadside burns can be challenging, but when done correctly, they’re not a big deal. It’s an accepted management practice that’s cheaper than spraying and cutting.

-Wes Gibbs, Jones County 2024

Stick with your burn plan. Even if you’ve spent a lot of time getting equipment and personnel to a burn site, if on that day conditions in the field do not meet your burn plan, DO NOT BURN. 

-Linn Reece, Hardin County, 2011

A small test burn at the anchor point will indicate fire and smoke behavior and the feasibility of continuing with the prescribed burn. 

-Jon Steege, Fayette County, 2011

We use strip head fires to speed up the burn without using a full-blown head fire. It works well with a smaller crew. 

-Jon Steege, Fayette County, 2011

Multi-use tanks and pumping systems should be thoroughly cleaned inside and out before being used for a new purpose. 

-Jon Steege, Fayette County, 2011

We try to vary burn seasons and intervals between burns so we aren’t adversely affecting any one set of desirable species. 

-Jim Uthe/James Devig, Dallas County

Appendix

Appendix thompsbb
A cyclist bikes at sunset on a road next to native roadside vegetation.

County Vegetation Management Survey

County Vegetation Management Survey thompsbb

Use this survey as a tool for evaluating existing roadside management practices. The results will identify the program’s strengths and weaknesses, and be a guide for shaping the direction of the program’s future management practices. The survey is primarily intended to be used by an IRVM steering committee. Responses can be subjective, varying widely from one person to the next. Interviewing roadside management personnel will add validity to the process. 

 Rate each of the following by circling all responses that apply. 

  1. Tree and brush control
    • Maintenance of sight lines
      • Very good
      • Adequate
      • Inadequate
      • Big need
    • Maintenance of recovery zone
      • Very good
      • Adequate
      • Inadequate
      • Big need
    • Removal of trees that present immoveable objects
      • Very good
      • Adequate
      • Inadequate
      • Big need
    • Removal of hazardous tree limbs
      • Very good
      • Adequate
      • Inadequate
      • Big need
    • Amount of tree cutting in general 
      • Well-balanced approach
      • Too aggressive
    • Quality of tree and brush cutting
      • Clean & professional
      • Not too bad
  2. Weed control
    • General perception of roadside weed control
      • Very good
      • Adequate
      • Inadequate
      • Big issue
      • Not an issue
    • Amount of roadside spraying being done
      • Very good
      • Adequate
      • Inadequate
      • Big issue
      • Not an issue
    • Effectiveness of roadside weed spraying
      • Good results
      • Making progress
      • No sign of improvement
      • Losing ground
    • Characterize the application of herbicides
      • Responsible
      • Inconsistent
      • Indiscriminate
    •  Do spray crews need to cover more of the county each year?
      • Yes
      • No
      • Not the main concern
    • Is most weed spraying completed during May, June and September when spraying is most effective?
      • Yes
      • No
    • When a landowner complains about roadside weeds, but the weeds in question are not considered much of a problem, do you...
      • Take advantage of the opportunity to explain the county’s IRVM program and weed control priorities 
      • Automatically spray the weeds
  3. Who does the roadside seeding? 
    • Private contractor
    • Private contractor does large jobs
    • Secondary roads
    • Conservation
  4. When is native vegetation used in roadsides? 
    • After nearly all road projects
    • High profile projects 
    • Ditch cleanouts
    • Wide rights-of-way
    • Not at all
  5. Equipment needs

    Consider working condition, current technology, appropriateness and availability of each of the following and recommend what equipment needs to be replaced or added.

    • Trucks
    • Tractors
    • Spray equipment
    • Chainsaws
    • Mowers
    • Seeding equipment
  6. Number of employees with:
    • Weed control as primary responsibility during spray season
    • Brush control as secondary responsibility year-round
    • Herbicide applicator certification
    • Chainsaw and boom mower experience
    • Vegetation management knowledge/background
    • Native plant establishment/management experience
    • Prescribed burn experience/certification
  7. How much is the county currently spending on:
    • Tree and brush control
    • Weed control
    • Seeding road projects
    • Erosion control measure installation
    • Weed commissioner salary
  8. Based on the responses to these questions, which of the following are recommended?
    • Hire a full-time professional roadside manager
    • Hire a 9-month assistant roadside manager
    • Hire more seasonal help
    • Hire better-qualified seasonal help
    • Free up more existing personnel for roadside management
    • All of the above

Position Description

Position Description thompsbb

_________ COUNTY, IOWA

POSITION DESCRIPTION


Position Title: Roadside Vegetation Manager

Department: County Engineer or County Conservation or Independent

Supervisor: County Engineer or Conservation Director or County Supervisors

Salary Range: $35,000–$45,000


Definition

A permanent, full-time position for the general implementation of the county’s Integrated Roadside Vegetation Management (IRVM) program and duties associated with all aspects of vegetation management within county secondary road right-of-way (ROW) corridors. Primary work activities are focused on the continued maintenance and development of safe travel corridors for vehicles and the application of sound ecological principles to manage desired vegetation types along those corridors.

Optional:

  • Will perform related duties as required by the county engineer.
  • Will work directly with parks and wildlife area managers to assist them with routine public land and facility management goals and objectives.

 Duties and Responsibilities

  1. Direct the assigned staff in the design and implementation of the county’s IRVM plan.
  2. Control noxious weeds in road rights-of-way, particularly those species identified by the county IRVM committee.
  3. Coordinate and assist with control and removal of woody vegetation along county roadways.
  4. Establish vegetation, primarily native, in cleaned, regraded and newly created ROW.
  5. Conduct prescribed burns in selected county road ROW.
  6. Conduct safety training for assigned staff.
  7. Perform all duties and responsibilities of the County Weed Commissioner.
  8. Develop a program of public information and education to promote public understanding of IRVM and wise land use practices that support IRVM objectives.
  9. Inventory and document plant communities and related conditions along county ROW.
  10. Manage those areas of native vegetation identified by the inventory process to improve diversity and overall health.
  11. Maintain accurate, up-to-date records of the following activities: herbicide application, seeding and reseeding, prescribed burning, tree and brush removal and timely handling of complaints from county residents and other government agencies.
  12. Assist with and perform scheduled and non-scheduled routine equipment maintenance and arrange with supervisor for non-routine work to be completed by private vendors.
  13. Direct and assist with production, harvest and processing of native seed for use in ROW seeding projects.
  14. Compile monthly individual and supervised staff work activity reports for all tasks completed.
  15. Keep records of maintenance performed on assigned equipment and facilities.
  16. Assist supervisor with annual budget preparation and expense tracking for ROW management operations.
  17. Submit applications to the Living Roadway Trust Fund and other funding opportunities.

Qualification Requirements

To perform this job successfully, an individual must be able to satisfactorily perform each essential duty. The requirements listed as follows are representative of the knowledge, skill and ability required.

  1. Ability to operate and maintain the necessary tools and equipment.
  2. Ability to identify native and introduced plant species, including noxious weeds.
  3. Ability to organize assigned work and develop efficient strategies to accomplish said work.
  4. Ability to establish and maintain effective working relationships with other staff, the general public, special interest groups and individuals from other agencies.
  5. Ability to operate personal computers and demonstrate or attain proficiency in Windows, Microsoft Word, Excel and the internet.
  6. Ability to continue professional training to remain knowledgeable of current issues, trends and management techniques.
  7. Ability to make minor repairs on equipment and facilities not requiring a trained, professional repair person.
  8. Ability to work a non-standard work week, including nights and weekends to accomplish the objectives of the position. 
  9. Ability to maintain accurate safety, work and equipment maintenance records.

The requirements and duties listed above are intended only as illustrations of the various types of work that may be performed. The omission of specific statements of duties does not exclude them from the position if the work is similar, related or a logical assignment to the position.

Education and Experience

A bachelor’s degree in a natural resource-related field and a minimum of two years practical work experience in natural resource/vegetation management or any equivalent combination of education, training and experience which provides requisite knowledge, skills and abilities for this position.

Knowledge of the tools and equipment required to perform the job.

Language Skills

  1. The ability to communicate effectively with co-workers and the general public.
  2. Ability to deal with the general public in a tactful and courteous manner.
  3. Ability to properly and effectively communicate verbally and in writing.

Reasoning Ability

  1. Ability to apply common-sense understanding to carry out instructions in written, oral or diagram form.
  2. Ability to apply common sense to solve problems or achieve work objectives.
  3. Ability to recognize work situations that require special attention.
  4. Ability to deal with problems involving several variables in standardized situations.

Certificates, Licenses, Registrations

  1. Valid Iowa Commercial Drivers License (within 60 days of hire date).
  2. Valid Iowa Pesticide Applicator License in category 6, Right-of-way and category 1A, Agriculture.

Physical Demands

The physical demands described here are representative of those that must be met by an employee to successfully perform the essential functions of this job.

  1. While performing the duties of this job, the employee is routinely required to stand, walk, sit, operate hand tools, kneel, stoop, balance and climb ladders and equipment. These activities may be required for two or more hours at a time during an 8–10 hour work day.
  2. The employee must routinely lift 50-pound objects 40 inches high and carry them for 15 yards.
  3. The specific vision abilities required for this job include: close vision, distant vision, color vision, peripheral vision, depth perception and the ability to adjust focus.

Work Environment

The work environment characteristics described here are representative of those an employee encounters while performing the essential functions of this job.

  1. While performing the duties of this job the employee may work around moving parts/equipment.
  2. The employee may work outdoors in extreme hot, cold, rainy, snowy and windy weather conditions.
  3. The employee may be exposed to dust, fumes and loud noises.

Comments

Must be insurable for driving under county insurance company policies.

Applicant will be subject to post-offer, pre-employment drug and physical testing.

 

The county is an Equal Opportunity Employer. In compliance with the Americans with Disabilities Act, the County will provide reasonable accommodations to qualified individuals with disabilities and encourages prospective employees and incumbents to discuss potential accommodations with the employer.

Generic IRVM Plan

Generic IRVM Plan thompsbb

______ COUNTY INTEGRATED ROADSIDE VEGETATION MANAGEMENT

General Plan

Section 314.22 of the Iowa Code, Integrated Roadside Vegetation Management, states:

It is declared to be in the general public welfare of Iowa and a highway purpose for the vegetation of Iowa's roadsides to be preserved, planted, and maintained to be safe, visually interesting, ecologically integrated, and useful for many purposes.

DEFINITION

Integrated Roadside Vegetation Management (IRVM)

A long term approach to vegetation management that:

  1. Systematically evaluates each area to be managed.
  2. Determines which plant communities best fit the area.
  3. Develops procedures that will encourage, enhance or re-establish native plant communities.
  4. Provides self-sustaining, diversified, visually interesting vegetation.
  5. Keeps safety and an improved environment as priorities.
  6. Utilizes the most beneficial methods to prevent or correct undesirable situations by disturbance or less than optimum vegetative ground cover.
  7. Enforces Chapter 317, Code of Iowa Noxious Weed Law.

INTRODUCTION

The prime purpose of road corridors is to transport people and goods safely and efficiently from one location to another. The prime purpose of roadside vegetation is to hold soil in place without creating hazards.

__________ County's vegetation management goals must meet certain safety and functional requirements before aesthetic, recreational, or economic considerations can be addressed. These are to maintain a clear zone recovery area, meet minimal sight distance requirements and provide for erosion control. We are also required by law to mow or otherwise control noxious weeds. 

Through the use of IRVM, we should be able to meet the prime purposes, provide a safe corridor for travel and address other desirable uses for roadside vegetation. 

The goals of the Integrated Roadside Vegetation Management Program are to: 

  1. Preserve and provide safe, functional and environmentally improved corridors of travel throughout the county.
  2. Utilize a long-term integrated management program that promotes desirable, self-sustaining plant communities in roadsides, drainage districts and other public lands in __________ County.
  3. Encourage those plant communities that are native to Iowa through preservation and re-establish whenever practical.
  4. Implement a brush control program within the roadsides and county drainage districts.
  5. Make more efficient and effective use of chemicals as a control method of undesirable plants.
  6. Enhance the scenic qualities of the roadsides and their value as roadside habitat.

PROCEDURES FOR INTEGRATED ROADSIDE VEGETATION MANAGEMENT

  1. Inventory sites to be managed, listing areas of desirable vegetation and those needing improvement.
  2. Determine the appropriate management methods needed.
  3. Determine the best time to implement management procedures and see that they are accomplished at that time. Temporary procedures may be needed to preserve an area before permanent methods can be utilized. 

INTEGRATED ROADSIDE VEGETATION MANAGEMENT METHODS

Integrated vegetation management includes the use of cultural, mechanical, biological and chemical practices. Each location must be evaluated to determine the method to be used. One or more of the following will be used:

  1. Cultural Methods

    Cultural controls can be achieved through the introduction and management of desirable plants to control noxious weeds and other undesirable plants. __________ County IRVM will use diverse native grass and forb mixes in their plantings. These diverse native plantings will be maintained and protected. Traditional lower gardening turf/lawn species may be used in clear zone areas or in front of private buildings at the landowner's request.

    Prescribed fire is recognized as a valuable tool in brush and invasive plant control and can be used to enhance and maintain native plant communities. __________ County recognizes the potential hazards relating to prescribed fire. Therefore roadsides will be burned only under the safest atmospheric conditions by burn crew personnel trained and certified in the use of fire. 

  2. Mechanical Methods

    This involves anything from tractor mowers for managing shoulders, weed control and planting maintenance for pruning shears, chainsaws and boom mowers for controlling brush and maintaining guardrails and the clear zone.

  3. Biological Methods

    This involves the use of animals, insects, bacteria or viruses to control plant growth. Natural enemies of noxious weeds could possibly be used in the ROW if necessary. Further research will be needed on other possible biological controls before the county will recommend them.

  4. Chemical Methods

    Selection of chemicals to be used shall be based on their label constraints and residual effects on the environment. They will be monitored to document their effectiveness and impacts upon target and non-target species. 

    The herbicide industry continually develops new chemicals with specific effects on specific plant species. These herbicides can be valuable tools for controlling undesirable plants on a short-term basis. __________ County herbicide applicators will be certified by the State of Iowa as public applicators in categories 1A and 6.

EDUCATION AND INFORMATION

As part of the county's IRVM plan, it will:

  1. Develop a public awareness campaign to gain support for integrated roadside management through media, established organizations, seminars and brochures.
  2. Obtain educational and informational material on IRVM to be presented in seminars and distributed to adjacent landowners, the general public, consultants and contractors.
  3. Provide guidelines and directives for contractors and others who seed, plant and maintain roadsides.
  4. Prepare and distribute instructions on preservation of desirable areas and treatment of areas that need improvement.
  5. Gather, develop, and distribute information with other jurisdictions, municipalities, counties and nonprofit organizations.
  6. Encourage research in all aspects of IRVM, e.g.: road design for improving IRVM, planting methods, management practices, seed sources, seeding rates, seed mixes, planting materials, etc.
  7. Encourage use of native seeds and plant materials.
  8. Document and map all aspects of the IRVM progress using GIS software.

This is a flexible plan that requires common sense interpretations with changes as necessary to fit the ever-changing complex circumstances realized in roadside vegetation management. 

 


County Supervisor/Chairperson

 


County Engineer


‌Date

 


Date

Sample Native Seed Mixes

Sample Native Seed Mixes thompsbb

Diversity mix

(mixes change slightly each year based on species availability and prices)

Grasses Pounds per acreSeeds per square foot
Big bluestemAndropogon gerardii1.55.50
Sideoats gramaBouteloua curtipendula2.55.50
Canada wildryeElymus canadensis2.03.80
SwitchgrassPanicum virgatum0.52.60
Little bluestemSchizachyrium scoparium2.513.80
IndiangrassSorghastrum nutans1.56.60
Rough dropseedSporobolus asper1.011.00
Total 11.5048.80

 

Forbs Ounces per acreSeeds per square foot
Lead plantAmorpha canascens0.80.29
Butterfly milkweedAsclepias tuberosa2.00.20
Canada milkvetchAstragalus canadensis1.60.62
White wild indigoBaptisia lactea1.00.04
Partridge peaChamaecrista fasciulata32.02.00
Prairie coreopsisCoreopsis palmata0.80.18
Purple prairie cloverDalea purpurea3.21.10
Showy tick trefoilDesmodium canadense0.80.10
Pale purple coneflowerEchinacea pallida4.40.53
Rattlesnake masterEryngium yuccifolium2.00.34
Ox-eye sunflowerHeliopsis helianthoides4.80.69
Roundheaded bushcloverLespedeza capitata2.00.37
Rough blazingstarLiatris aspera0.80.29
Prairie blazingstarLiatris pycnostachya4.81.21
Wild bergamotMonarda fistulosa1.62.57
Stiff goldenrodOligoneuron rigidum0.80.75
Foxglove penstemonPenstemon digitalis2.05.97
Large-flowered penstemonPenstemon grandiflorus1.00.32
Yellow coneflowerRatibida pinnata4.83.31
Black-eyed SusanRudbeckia hirta3.26.76
Sweet black-eyed SusanRudbeckia subtomentosa0.40.39
Wild petuniaRuellia humilis1.60.19
Compass plantSilphium laciniatum1.20.02
Smooth blue asterSymphyotrichum laeve0.40.51
New England asterSymphyotrichum novae-angliae0.81.21
Ohio spiderwortTradescantia ohiensis2.40.44
Hoary vervainVerbena stricta0.80.51
IronweedVernonia fasciculata0.40.22
Culver's rootVeronicastrum viginicum0.47.35
Golden AlexandersZizia aurea1.60.40
Total 84.4038.88

 

Wet species Ounces per acreSeeds per square foot
Swamp milkweedAsclepias incarnata2.80.31
Blue jointCalamagrostis canadensis1.27.71
Brown fox sedgeCarex vulpinoidea3.27.35
SneezeweedHelenium autumnale0.61.79
Great blue lobeliaLobelia siphilitica0.44.59
Mountain mintPycnanthemum virginianum0.42.02
Dark green bulrushScirpus atrovirens3.233.79
Blue vervainVerbena hastata0.40.85

Wet species bagged separately for use in moist ditch bottoms.

 

Ditch clean-out mix

Grasses Pounds per acreSeeds per square foot
Big bluestemAndropogon gerardii1.55.50
Sideoats gramaBouteloua curtipendula2.55.50
Canada wildryeElymus canadensis2.03.80
SwitchgrassPanicum virgatum0.52.60
Little bluestemSchizachyrium scoparium2.513.80
IndiangrassSorghastrum nutans1.56.60
Rough dropseedSporobolus asper1.011.00
Total 11.5048.80

 

Forbs Ounces per acreSeeds per square foot
Swamp milkweedAsclepias incarnata2.80.31
Partridge peaChamaercrista fasciulata16.01.00
Purple prairie cloverDalea purpurea3.21.10
Pale purple coneflowerEchinacea pallida4.40.53
Rattlesnake masterEryngium yuccifolium1.00.17
Ox-eye sunflowerHeliopsis helianthoides4.80.69
Yellow coneflowerRatibida pinnata4.83.31
Black-eyed SusanRudbeckia hirta3.26.76
Total 40.2013.87

Foliar and Basal Bark Brush Control Herbicide Recommendations

Foliar and Basal Bark Brush Control Herbicide Recommendations thompsbb

Foliar Brush Control Herbicide Recommendations

SpeciesChem-Trol/VMS (2002)UAP/Timberland (2002)Roadside Manager Recommendations (2011)
Boxelder

Escort 2 oz.

Tordon K

Tordon K

Garlon

Escort XP

Garlon/Escort
Chinese Elm

Escort 2 oz.

Garlon 4

Krenite

Tordon K

Garlon

Dicamba

Escort XP

Tordon 101

Garlon/Escort
Cottonwood

Escort 2 oz.

Garlon 4

Krenite

Escort XP

Garlon

Krenite

Dicamba/Vanquish

Patron 170

Garlon/Escort
Dogwoodn/an/aGarlon/Escort
Eastern Red Cedar

Escort 3 oz.

Tordon K with non-ionic surfactant

Escort XP

Tordon K

Garlon/Escort thorough coverage not needed.

Krenite high-volume treatment seems to work on small cedars (< 8 ft.) in July. This may be a function of the surfactant.

Green Ash

Krenite

Escort

Krenite/Tordon K

Escort XP

Garlon

Garlon 4/Escort

Garlon

Honeysucklen/an/a

Roundup works well but kills understory.

Garlon/Escortprovides partial control; seems to work best when fall-applied. Surfactant improves results. Two applications in the same year (spring and fall) provides better control. 

Tordon

LocustTordon K

Tordon K/Tordon 101

2,4-D/Dicamba

Garlon/Escort

Krenite

Milestone

Maple

Escort 2 oz.

Krenite

Tordon K

Garlon 4

Tordon K

Arsenal

Krenite or Garlon +

Tordon or Escort

Garlon/Escort
Mulberry

Escort 2 oz.

Garlon

Krenite

Tordon K

Escort XP

Stalker/Arsenal

Krenite

Garlon/Escort

Garlon

Oakn/an/aGarlon/Escort
Olive, Autumnn/an/aGarlon/Escort provides partial control; seems to work best when fall-applied.
Plum

Escort 2 oz.

Garlon

Tordon

Krenite

Escort XP

Garlon

Tordon K

Krenite

Garlon/Escort
Sumac

Escort

Arsenal

Escort XP

Garlon

Tordon K/Tordon 101

Patron 170

Garlon/Escort
Willow

Escort 1 oz.

Garlon 4

Krenite

2, 4-D

same as cottonwood

Garlon/Escort

Krenite

Roadside manager notes (2011) — Foliar herbicide:

  • Garlon/Escort is a common mix for brush control. Where Garlon (triclopyr) is noted, either Garlon 3A (amine formulation) or Garlon 4 (ester) can be used. Garlon 4 is usually more effective but in hot weather can volatilize drift and affect non-target species. 3A is non-volatile and usually considered the best choice for hot weather. 
  • We quit spraying Tordon in roadside situations due to standing water and high water tables.
  • Arsenal usually kills cool season grass, which can eventually create thistle problems. We limit its use to Japanese Knotweed.
  • We've had good luck with Opensight at 3.3 ounces per acre plus an additional 1 ounce per acre of Escort on all of these trees.
  • Honeysuckle control is different. When isolated patches are found, consider basal treatment.

Basal Bark Brush Control Herbicide Recommendations

Species(2002)Roadside Manager Recommendations (2011)
Black LocustGarlon 4Garlon 4
Boxelder

Pathfinder 2

Garlon 4

Garlon 4
Chinese Elm

Pathfinder 2

Garlon 4

Garlon 4
CottonwoodGarlon 4 (+ Stalker optional)Garlon 4
Eastern Red Cedar

Pathfinder 2 

Garlon 4 (poor)

25% Garlon 4 (works fair-to-well on trees < 8 feet)
Honeysucklen/aGarlon 4 (+ 1% Stalker, optional. Hacking bark with pocket saw before spraying improves results. Cut stump treatment is best for bigger plants.)
Mulberryn/aGarlon 4 (hacking bark with pocket saw before spraying may improve results)
OakGarlon 4Garlon 4
PoplarGarlon 4Garlon 4
Sumac

Pathfinder 2

Garlon 4

Garlon 4
WillowStalker + Garlon 4Garlon 4 (no need to include Stalker)

Roadside manager notes (2011) — Basal bark herbicide:

  • We've started adding about 0.5–1% Stalker to our 25% Garlon 4 mix. We used to add 3% Stalker, but our "ring of death" seemed to last for three or more years rather than just one.
  • It helps to hack up thick- or corky-barked tress and trees > 2 inches in diameter.
  • For most trees, we use 2.5 gallons Garlon plus 4 quarts Stalker plus 12.5 gallons diesel fuel or basal oil to make about a 15 gallon mix.

2002 herbicide recommendations taken from Tree and Brush Control for County Road Right-of-Way.

Iowa Pesticide Applicator Licenses and Certifications

Iowa Pesticide Applicator Licenses and Certifications thompsbb

Iowa Pesticide Applicator Licenses and Certifications 

Certified Applicators 

Each individual who applies pesticides for a state or county agency, municipal corporation or other government entity is required to be certified. Certified public applicators may obtain a one-year certification for $10 or a three-year certification for $15. Certifications are valid only when associated with a valid licensed agency. Written examinations are required for first-time applicators. Written exams are also required for individuals adding on certification categories and those persons choosing not to maintain continuing instruction credit hours.

The core examination and appropriate category test(s) must be successfully passed before application for certification can be made. Additional categories may be added anytime with no extra charge. Any category will carry the same expiration date as the card on which it is added. Each certified individual must be listed as an applicator under a current Iowa pesticide applicator license for that certification to be valid. 

Renewal of Applicator Certifications 

Each applicator is placed on a three-year “qualification cycle.” During those three years, an applicator may maintain a single-year certification by submitting a one-year fee and renewal form (certification renewal forms are provided by the Pesticide Bureau). A 30-day grace period from the date of expiration will be allowed for the renewal of the certification. At the end of the qualification cycle each applicator must indicate a method of renewal by: 

  1. Declaring that at least two hours of continuing instruction for each certified application category has been received for each of the previous three years and verification of having received training is on file with the applicator’s employer; or, 
  2. Completing written tests at the end of the third year of the “qualification cycle;” or, 
  3. Maintaining a combination of training and testing. 

Note: An applicator who misses two hours of training for any one category for any one year is required to complete written tests for that particular category. There are no provisions for “making up” missed continuing instruction hours to avoid the written test. 

Written applicator tests are offered daily, Monday through Friday from 9 a.m. to 3 p.m. at the Wallace Building at East Ninth and Grand in Des Moines. If a group of ten or more is involved, please call (515) 281-4339 or (515) 286-5601 and make an appointment. Otherwise, no appointment is necessary. Photo identification is required. Tests are also offered on a limited basis at some cooperative extension service area offices. Please contact either the area office or the Pesticide Bureau for a current testing schedule.

Contact Information 

Licensing & Certification

Certification Testing Information

Pesticide General Information

515-281-5601

515-281-8591

515-281-8591

Restricted-use Pesticide Recordkeeping 

These rules apply to both certified private and commercial applicators. The Iowa Pesticide Act requires applicators to keep records of all pesticide applications for 3 years. The federal regulations require pesticide applicators to record the following information within 14 days of the restricted use pesticide application: 

  • The brand or product name and the EPA registration number of the restricted use pesticide that was applied. 
  • The total amount of the restricted-use pesticide applied. 
  • The location of the application. 
  • The size of the area treated. 
  • The crop, commodity, stored product or site to which the pesticide was applied. 
  • The month, day and year on which the restricted-use pesticide application occurred. 
  • The name and certification number of the certified applicator who applied the restricted-use pesticide.

More information can found in this IDALS document. 

Sample Press Release

Sample Press Release thompsbb

P R A I R I E  C O U N T Y  E N G I N E E R

1 2 3 4  H I G H W A Y  1

P R A I R I E  C I T Y ,  I O W A  5 4 3 2 1

5 5 5 - 1 2 3 - 4 5 6 7


FOR IMMEDIATE RELEASE

Date: March 1, 2024

Contact: Mike Jones, Prairie County Roadside Manager – 555-123-4567

 

Prescribed Burning in County Rights-of-way

Prairie County IRVM will be conducting prescribed burns in county road rights-of-way during the next few months. Prescribed burns are an effective resource management tool utilized to discourage the growth of weeds and woody vegetation, while promoting the growth of desired native vegetation in roadside prairie sites. All staff members are certified in wildland firefighting and take all necessary safety precautions to minimize the risks associated with a prescribed fire. Please use caution when approaching a burn site as staff members and equipment may be near the traveled portion of the road.

For more information, contact the IRVM office at 555-123-4567.

Sample Adjacent Landowner Notification

Sample Adjacent Landowner Notification thompsbb

P R A I R I E  C O U N T Y  E N G I N E E R

1 2 3 4  H I G H W A Y  1

P R A I R I E  C I T Y ,  I O W A  5 4 3 2 1

5 5 5 - 1 2 3 - 4 5 6 7


MEMO


TO: RESIDENT

FROM: MIKE JONES

DATE: MARCH 10, 2024

RE: CONTROLLED BURNING IN RIGHT-OF-WAY

 

(address)

In order to encourage the establishment of native plant communities in our roadsides, different management techniques must be used along with our more traditional methods of mowing and spraying. Prescribed burning (not to be confused with wildfire) is any fire ignited by management actions to meet specific objectives. Goals of prescribed burns in terms of roadside management include stimulating growth of desirable species such as native grasses and flowers, impeding growth of undesirable species such as weeds and woody vegetation, and giving desirable species a competitive advantage over other species. In some instances, a prescribed burn may replace the need to use herbicides in the ROW. 

A prescribed burn for the right-of-way in the vicinity of your residence is scheduled for this spring. The burn will be conducted only by properly trained personnel and only under the safest conditions. The purpose of this memo is to notify you that a) a prescribed burn will take place, b) smoke will be produced in and around the vicinity of the burn for a short time, and c) this action may require minor traffic control around your residence. 

 

Specific location:

Right-of-way on Apple Avenue between 120th Avenue and 130th Avenue

For any questions, comments, or concerns about this notice, please contact:

Mike Jones, Roadside Manager/Weed Commissioner

Prairie County Secondary Roads Department

1234 Hwy 1

Prairie City, IA 54321 

555-123-4567

Sample Burn Site Spreadsheet

Sample Burn Site Spreadsheet thompsbb

Burn history

Site ID #

Location

Wind direction

Last burn

1996-7N side 150th W of Juniper

S

4/24/2014
1995-10E side Tulip Ave S of 290th

W

12/10/2014
1996-17S side 150th W of Juniper Ave

N

4/15/2018
1997-7S side 300th W of Sumac Ave

N

3/31/2020
1997-9W side Sumac Ave S of B20

E

3/31/2020
1992-2S side 130th J-I

N

4/1/2020
2002-5W side Violet Ave N of 150th

E

10/15/2020
1994-5N side 120 S-T

S

11/15/2020
1998-1Triangle @ 260th & Finch Ave

NW

11/23/2020
1996-13S side B15 W of Prairie Ave

N

4/7/2021
1991-1S side 265th W of Oak Ave

N

4/12/2021
1995-13S side 320th E of Bluebird Ave

N

4/13/2021
1996-12S side 310th E of Phlox Ave

N

4/13/2021
1996-1N side 160th E of Robin Ave

S

4/15/2021
1995-20N triangle Basswood Ave & 300th

SE

4/6/2022
2001-5S side 200th E of Maple Ave

N

4/12/2022
2002-4S side of 210th W of Nuthatch Ave

N

4/12/2022
1995-17S triangle 320th & Killdeer Ave

E

4/17/2022
1995-21S triangle Dogwood Ave & 300th

NE

4/17/2022
1997-5E side Tulip Ave N of 290th

W

4/19/2022
1994-1S triangle 150th & Violet Ave

W

4/20/2022
1994-6S triangle 130th & Eagle

N, W

4/20/2022
1994-4E side Tulip Ave S of 320th

W

4/21/2022
1995-12E side Tulip Ave S of 320th

W

4/21/2022
1997-8E side Sparrow Ave S of 300th

W

4/21/2022
1995-15S side 330th E of Larkspur Ave

N

4/25/2022
2000-2S side 330th W of Prairie Ave

N

4/25/2022
2001-1S side 250th T-V

N

4/25/2022
2004-2E side Tulip Ave N of 170th

W

11/20/2022
1998-4Bridge 290th E of Spruce Ave

S

11/22/2022
2003-3Triangle @ Apple Ave & 220th

S

11/22/2022
2005-2W side Ash Ave N of 210th

E

11/22/2022
1995-2S side 150th E of Hickory Ave

N

4/9/2023
1995-22S side 150th W of Walnut Ave

N

4/9/2023
1995-4S side 160th E of Sycamore Ave

N

4/9/2023

Last updated: 5/1/2023

Sample Burn Plan

Sample Burn Plan thompsbb

Prescribed Burn Management Plan

Location: West side of Apple Ave. between 120th St. and 130th St.

Prescribed burn parameter for this location

Temperature: 40–70 F

Wind direction(s): East or southeast

Wind speed: < 15 miles per hour

Relative humidity (%): > 30%

Personnel requirements: 1 crew boss, 1 additional

Equipment requirements: 1 pump truck (300 gallons), hand tools, 1 backpack sprayer

Potential hazards:

  • Wood utility poles (x6)
  • Phone box 20 yds. north of farm drive
  • Corn stubble in adjacent field (tilled)
  • Stop sign
  • Plastic culvert under farm drive

Prepared fire breaks required

Description:

  • Wet line near intersection of Apple Ave. and 120th St.
  • Wet lines around potential hazards

Potential anchor points: Northwest or southwest corners

Special concerns:

  • Heavy traffic on Apple Ave. after 3 p.m.
  • Acreages/farms located to the west and northwest

Notes:

Smooth brome abundant on the north end – early spring burn desired

  

Emergency phone:

Local fire district:

‌Conservation Board Office

Prairie City Fire Department

555-111-5678

555-111-8765

Sample Weather Data

Sample Weather Data thompsbb

Prescribed Burn Weather Information

Location: West side of Apple Ave. between 120th St. and 130th St.

Date: April 18, 2024

Personnel:

  • Crew boss: Mike Jones
  • Crew: James Smith

Forecasted weather data

Source: NOAA

Forecast time frame: 9–11 a.m.

Temperature: 60–68 F

Relative humidity (%): 55–62%

Dewpoint: 32 F

Wind direction: Southeast

Wind speed: 7–10 mph

Cloud cover: Partly cloudy

Beginning on-site weather data

Time: 9:35 a.m.

Temperature: 64 F

Relative humidity (%): 58%

Dewpoint: 32 F

Wind direction: ESE

Wind speed: 8–10 mph

Cloud cover: Mostly sunny

Ending on-site weather data

Time: 10:15 a.m.

Temperature: 66 F

Relative humidity (%): 53%

Dewpoint: 30 F

Wind direction: SE

Wind speed: 8–10 mph

Cloud cover: Partly cloudy

 

Notes: 90% burn – approximately 2 acres

Print Resources for Roadside Managers

Print Resources for Roadside Managers thompsbb

Native plant and seedling guides

  • An Illustrated Guide to Iowa Prairie Plants. Christiansen, P. and M. Muller. 1999.
  • Central Region Seedling ID Guide for Native Prairie Plants. USDA - NRCS Elsberry Plant Materials Center and the Missouri DOC. 2005.
  • How to Know the Grasses. Pohl, Richard W. 1978.
  • The Prairie in Seed: Identifying Seed-Bearing Prairie Plants in the Upper Midwest. Williams, D. 2016.
  • The Prairie Seedling Guide, 2nd Ed. Bockenstedt, P. 2007.
  • Roadside Plants and Flowers. Edsall, M. 1985.
  • The Tallgrass Prairie Center Guide to Seed and Seedling Identification in the Upper Midwest. Williams, D. 2010.
  • Tallgrass Prairie Wildflowers: A Field Guide to Common Wildflowers and Plants of the Prairie Midwest. Ladd, D. and F. Oberle, 1995.
  • The Vascular Plants of Iowa. Eilers, L. and D. Roosa. 1994.
  • Wetland Plants and Plant Communities of Minnesota and Wisconsin, 2nd Ed. Eggers, S. and D. Reed. 1997.
  • Wildflowers of the Tallgrass Prairie, The Upper Midwest, 2nd Ed. Runkel, S. and D. Roosa. 2010. 

Restoration and Management guides 

  • A Practical Guide to Prairie Reconstruction. Kurtz, C. 2001.
  • The Ecology and Management of Prairies in the Central United States. Helzer, C. 2009. 
  • The Tallgrass Prairie Center Guide to Prairie Restoration in the Upper Midwest. Smith, D., D. Williams, G. Houseal and K. Henderson. 2010.
  • The Tallgrass Prairie Center’s Native Seed Production Manual. Houseal, G. 2007.
  • The Tallgrass Restoration Handbook, Revised Ed. Packard, S. and C. Mutel. 2005.
  • Tree and Brush Control for County Road Right-of-Way. Williams, W. 2002.

Weed and weed seedling guides