Roadside vegetation provides a valuable protective barrier to prevent pavement erosion, but it must be managed to keep weeds from creeping onto shoulders, roots from cracking asphalt, brush from obstructing sight lines as well as for the beautification of America’s highways. No matter the stage of a vegetation management plan, it’s important to structure goals around advice from local, trusted university extension specialists. These experts know the lay of landscape and have tested countless weed control products and application time to help determine the most effective and inexpensive vegetation management plan for roadways.
To hear what university cooperators and researchers are recommending in 2005, I interviewed three university extension specialists on the benefits of roadside integrated vegetation management (IVM). If there is one type of person that roadside vegetation managers rely on, it’s a specialist like Dr. Tim Murphy, Dr. Dearl Sanders and Art Gover.
Murphy is a professor in the Crop and Soil Sciences Department at the University of Georgia. Specializing in vegetation management weed science, he researches weed control for roadside winter annuals and summer perennial grasses.
Sanders is the resident coordinator and professor with the Louisiana State University Agricultural Center. He has been researching vegetation management for 25 years. His current research and extension responsibilities focus on forages, noncrop (roadsides, rights-of-way, etc.) and aquatics. He also is serving as academic advisor to the National Roadside Vegetation Management Association. Gover is a research support associate for the Roadside Vegetation Management Research program at Pennsylvania State University. This program has been investigating right-of-way management techniques since 1985, helping the Pennsylvania Department of Transportation Bureau of Maintenance find the best IVM plan.
Green with knowledge
The roadside vegetation management industry is seeing an upturn in advanced precision and efficiency technologies. For many agencies, this means switching to an IVM program. An IVM program based on herbicides is the most effective and efficient approach to making roadsides safer and more aesthetically appealing.
Whether enhancing an IVM program or trying to discern how to best get one off the ground, Murphy, Sanders and Gover’s industry insight helps provide the facts needed to see the most return on roadside vegetation management.
The following are highlights of a roundtable discussion with the industry experts.
What are the key issues that roadside vegetation managers are facing?
Murphy: The main problem roadside VM managers are facing is proper application and timing. There is also a continuous need to use herbicides with different modes of action to prevent the development of herbicide-resistant weeds.
Sanders: Ninety-five percent of spraying in Louisiana is directed at Johnsongrass. Roadside vegetation managers are seeking ways to get rid of this tall-growing native grass in favor of bermudagrass and bahiagrass.
Gover:There is an expanding palette of species that are invading roadsides and increasing public pressure to control them, but the resources that are available to treat them are nonexpanding.
Are there any new vegetation management industry trends that roadside managers should be aware of?
Murphy: Herbicide injection trucks have become an industry standard. They offer flexibility where herbicides are applied, as well as which ones can be used.
Sanders:Many roadside managers are using global positioning systems (GPS) to track where and when they have sprayed. By using the GPS on the application trucks, they can keep a good record of accountability for the areas that have been treated.
Gover: As the public becomes increasingly aware of the impact of invasive species, roadside managers need to pay more attention to the “good neighbor” aspect of roadside vegetation management. Management programs need to address not only species that are acutely problematic to the DOT, but to the adjacent landscape.
How has the concept of IVM changed the way roadside managers tackle their vegetation management programs?
Murphy:Mowing is still a vital component of any roadside vegetation management program. Mowing improves the appearance of the roadside, and when used in conjunction with herbicides will result in a high-quality, attractive roadside.
Gover: IVM allows roadside managers to take a structured approach to commonsense management. It’s like a business with a sound strategic plan—it helps vegetation managers manage more effectively and preventively.
What are the benefits of implementing an IVM program? What are the challenges?
Murphy: The benefit is that roadside herbicide application is less expensive than mowing. There is an immediate cost savings. There are also safety hazards that can be avoided by mowing less. Mowers are slow and can sometimes sling objects on roadsides up at passing vehicles. The challenge is that many roadsides are near crop areas and roadside VM managers cannot always use the type of herbicides they want.
Sanders: The cost of maintaining tractors, clippers and bush hogs is much more than applying herbicides. Applying herbicides twice a year and mowing twice a year is much less expensive than mowing eight or nine times a year.
Gover:The challenge is if the existing program is more along the lines of “fighting fires.” It’s hard to devote funds to a new program—especially in areas that don’t seem to be that problematic. Convincing stakeholders to take a more preventive, or maintenance, approach can be very difficult when the program is still in a control phase.
Can you provide some general guidelines for roadside managers to follow for a successful IVM?
Murphy: The No. 1 guideline is to get a properly trained applicator. Training the applicator in the application vehicle is absolutely critical. We have excellent herbicides and excellent equipment, but the applicator needs to know when to cut on and cut off the spray.
Gover:The applicator is the key to the operation. It’s beneficial when vegetation managers take training above and beyond licensing. Each manager should conduct additional training so that their applicators understand the specific objectives of the program, the intricacies of their equipment and the capabilities of the herbicides. This allows the applicator to make informed, sound decisions out in the field.
What advice do you have for managers who are trying to convince upper management to make the switch to IVM?
Murphy: Speak with other roadside VM managers and discuss their experiences. Focus on the cost-benefit ratios and look at the statistics. Review the cost of maintaining tractors and bush hogs while using mowing alone.
Sanders: Fortunately we don’t have much of a problem with that in Louisiana. We have nearly 60 in. of rain every year, so convincing upper-level management to implement a program that includes herbicides is easy.
Gover: Expand your time frame and expand your list of partners. IVM provides more stable plant communities that require less maintenance effort. Work with natural-resource agencies and advocacy groups to create plant communities that can provide benefits beyond reduced maintenance. An IVM program is easier to sell to management when you have support outside your own institution.