United States Department of Transportation - Federal Highway Administration FHWA HomeFeedback

10 IRVM Tools You Can Use

Minnesota signs Wildflower Routes1. PRESERVATION or saving the pieces should be your first choice to save time and money. What if you already have native grasses and wildflowers and just do not know where? What if you stopped mowing for one season to identify what is in the right-of-way? Your State botanists can help you determine if the vegetation is worth saving. If it is a quality remnant, you just saved a piece of natural history, more valuable than any you could plantÉ..and at no cost or worry. States like Delaware, Missouri, Minnesota, Wisconsin, and California have already done this. Their remnants are now signed for the traveling public and mowed less often, actually saving money.

2. MAPPING is simply a way to inventory what exists on your rights-of-way. Only if you know what is there can you easily make practical management decisions. A number of States have done mapping, including West Virginia, Minnesota, Oregon, Oklahoma, Kansas, Iowa, Missouri, and Texas to some extent. Oregon signs endangered species sites, coded for maintenance crews. Minnesota signs remnants to benefit crews and the traveling public. Knowing where endangered species are located, or where native remnants need protection, or where a new weed infestation occurs will help you plan ahead. A number of mapping methods exist. Call your State Natural Heritage Program to learn what has already been done in your State

NRVMA's tips for planning.3. STATEWIDE PLANNING can be based on inventorying all vegetation, including invasives to contain, natives to protect, and endangered species. With this baseline of information, you can plan how to manage for years to come. This information will also be useful in obtaining a fair share of the budget. Some State DOTs are using Global Positioning Units to document the locations of vegetation to be considered. This information is then entered into a GIS or graphic information system that consists of a series of map overlays aimed at giving decision-makers both the details and context of any given segment of roadside. With this information, you can then decide which tool to use in vegetation control and when. Top this program with careful record keeping, and you can determine what methods are successful over time.

Wisconsin reduces mowing4. MOWING as weed control should be well-timed. Spot mowings that target Canada thistle and other noxious weeds on the roadside are less costly than blanket mowings. Avoid mowing too short, thus scalping the plants and soils and inadvertently causing more weeds to invade. Avoid flail mowers, unless your intention is to disturb the soil for possible seeding operations. Mowing from right-of-way fence to right-of-way fence is no longer a common practice. Mowing just to keep the equipment occupied is not fiscally feasible. There are too many tasks stacking up for your limited crews. Reduced mowing is now possible. Mowing one or two widths off the pavement edge to provide a recovery zone for errant vehicles is important. Studies show that woody plant invasion of clear zones and backslopes takes many years before becoming hazardous to travelers. A Rutgers study suggests that crews might mow the entire ROW once every five years to prevent tree growth in forested regions, thus minimizing disturbance of the ROW and increasing small mammal and bird habitat. Less mowing also saves maintenance dollars which makes this a win-win-win idea.

Computerized sprayers increase safety5. HERBICIDES continue to be an important tool in our toolbox. For some invasive plants, spraying is the only answer. Crews now have the computerized equipment and knowledge to be able to target weeds, use less product per acre, and document all conditions and location of the job. In other words, we can spray more safely with less impact to the environment and desirable plant species on the project. Be smart and careful. Annual State applicator trainings continue to educate crews in best practices.

School kids celebrate the release of purple loosetrife beetles6. BIOCONTROLS already exist for purple loosestrife, leafy spurge, knapweed, and musk thistle. Kudzu could be next. The United States Department of Agriculture has spent time and money in introducing safe biocontrols for some of our toughest noxious weeds. In Tennessee, the DOT was able to reduce musk thistle infestations by 95% with one such biocontrol beetle. Biocontrols are a relatively inexpensive and safe alternative to blanket spraying of large populations of invasive species. Because most invasive plants outcompete desirable plants and appear to have left their natural competition behind in their country of origin, finding and applying these biocontrols is logical and useful. This tool can also be a great public awareness event to help your public understand the work you do.

Training is everything7. PRESCRIBED BURNS have been used by land managers for over 25 years in modern history. The value of a well-timed and placed burn of native vegetation has been apparent for many generations in this country alone. The procedure is practically explained by Wayne Pauley in his How to Manage Small Prairie Fires, 1988. However, never attempt a roadside burn without training from an agency that has a history of this vegetation management method. Even when site conditions appear to be perfect, winds can shift and throw the procedure into chaos. After learning how to burn, and acquiring the appropriate equipment, safety plans must be done. How will traffic be advised? How will cars move through the burn? What and how will you tell the public? A water truck and local firefighters should always be on alert for the event. A safe burn is the only acceptable burn, or this tool will be lost.

Goats appear to be an inexpensive and effective tool for knapweed on an inaccessible watershed slope in Oregon8. GRAZING GOATS can safely be used for vegetation management! A number of States including New Mexico, Oregon, and Montana have discovered the cost-effectiveness and success of this tool. Herds of goats can be fenced or trained to stay within the roadside as they munch their way through vegetation including invasives. Remember sheep were once the tool used to "mow" the White House lawn. Much remains to be learned.

9. NATIVE PLANTINGS that are well-established and undisturbed are an excellent defense against nonnative plant invasions. Because native plantings have erosion control value, wildlife value, low maintenance, biodiversity, and natural heritage benefits, native plantings are another tool in the toolbox.

Iowa DOT plants a diversity of grasses and flowers like theseNative plant restorations began in the United States some sixty years ago. Some of these have been studied for decades. Here are a few insights learned from the Curtis Prairie in Wisconsin:
1. If weeds are not eliminated before planting, they will persist for decades.
2. The number of species planted defines the diversity of the site long into the future, unless the project is adjacent to a natural area, from which native propagules can travel.
3. On projects with varied microclimates, a number of mixes might be necessary. A buckshot seeding, of one mix fits all, is likely to fail because xeric species cannot move if they die in a wet spot, etc. Some species are generalists, but not many.
4. Local seed, seedlings, or sods are more successful than seed from far away locations.

Education for crews and the public, a UDOT poster10. INFORMATION SHARING includes activities such as:
a. Visit the Utah Dot Vegetation Management Academy for a good training example.
b. Develop plant identification tools like Maryland's field guides and Utah's posters.
c. Wisconsin holds an annual workshop to educate consultants and contractors.
d. Attend other land managers' training sessions.
e. Network with counterparts in other agencies.
f. Become a member of NAWMA, NRVMA, IECA, and/or SER.
g. Expand annual herbicide training to include all tools with hands-on demonstrations.
h. Use conservation group information (Pheasants Forever, Ducks Unlimited, The Nature Conservancy, Natural Areas Association, Native Plant Societies, EPPCs, and Garden Clubs).
i. Take advantage of university research and offer research sites on highway row.
j. Learn from successes in other states, avoid wasting time/$$$ by convening at the border.
k. Check out vegetation websites.
l. Improve public awareness through media, volunteer projects, and public meetings.

 


Table of Contents | Previous | Next

This page last modified on August 4, 2004


FHWA Home | Feedback
FHWA
United States Department of Transportation - Federal Highway Administration