Pennsylvania is a wellspring of history, business and architecture. As the second state to enter the union, it’s no surprise it chose the motto “Virtue, Liberty and Independence,” and its nickname, “The Keystone State.”

When it comes to vegetation management throughout the state, the Pennsylvania Department of Transportation (PennDOT) follows its statewide tradition for excellence.

The Pennsylvania road system covers more than 40,000 miles—the fifth-largest number of road miles of any state in the country. Mike Maurer, a 33-year industry veteran, maintains the vegetation management programs for the right-of-ways (ROWs) in Pennsylvania Engineering District 12. His duties for PennDOT include taking care of welcome centers and overseeing vegetation management along 3,800 road-miles within his district.

Maurer has long recognized the value that herbicides bring to his roadside maintenance operations. He’s used a combination of chemical and mechanical control to maintain right-of-way turf in his district for the past 15 years. After seeing many products come and go, and through years of research, Maurer has developed one of the most sophisticated and successful vegetation management programs in the country.

More than meets the eye

Maurer takes a big-picture approach when it comes to managing his roadsides. “I see everything as part of a greater management system and try not to focus on one particular species without first assessing how each part fits into one of my main goals: maintaining clean competitive turf along roadside corridors; clearing brush from right-of-ways; and managing bare-ground areas underneath guardrails.

As a general rule, Maurer aims to have cool-season fescue grasses lining his roadsides. While mowing is an effective way for PennDOT to maintain fescue height in some areas, Maurer also uses a plant growth regulator (PGR) program where steep grades make it difficult or impossible to mow. The PGR program provides not only seed head suppression, but also grass growth suppression to keep tall and densely growing grasses from creating a hazard. By treating with herbicide in late April to early May, he is able to maintain desirable fescue at a controlled height, which ensures clear road visibility and upholds the aesthetic quality of the roadsides.

“Many of our primary roadways throughout the district include steep hills and sudden curves,” Maurer said. “If grass or brush along these corridors grew to unruly heights, drivers would not be able to see around corners. However, these areas are also impossible to mow. To keep the grass from growing too tall, we spray it once every spring.”

Maurer also relies upon selective herbicides in conjunction with his PGR herbicide application for weed control in roadside turf. Weeds like mile-a-minute weed, foxtail, poison hemlock, a variety of thistles, ragweed, teasel and many other weeds can quickly overrun ROW zones in Pennsylvania if not treated quickly, but desirable plants need to stay in place to avoid erosion and other soil issues.

Revisiting PGR

One thing Maurer learned from many years on the job is that it always pays to try something new. One of the reasons PennDOT has been a leader in vegetation management programs for nearly 20 years is the department’s strong working relationship with roadside vegetation management researchers at Penn State University, where new technologies are tested every day.

While the district had used PGR technology since 1996, in 2004 Maurer began testing two newer products, Plateau herbicide and Overdrive herbicide from BASF Professional Vegetation Management (ProVM), to see if these herbicides would provide equal or better growth regulation and broadleaf weed control than his current PGR herbicide mix. Maurer worked with sales specialist Mike Fleming and market development specialist Dan Beran to create research areas in right-of-way areas.

Working closely with Penn State researchers Art Gover, John Johnson and Dr. Larry Kuhns, test plots were established to check the efficacy of Plateau and Overdrive on grasses and broadleaf weeds.

In 2005, the team discovered some unexpected results. Not only did they find control of mile-a-minute weed, but Plateau also controlled late-season foxtail, an undesirable grass that germinates from late May throughout summer and had been difficult to achieve season-long control with the existing bare-ground herbicides. Maurer noticed that Plateau provided better foxtail control as well as growth suppression and seed head control. Overdrive worked as well, if not better, than other tested products to control mile-a-minute weed along with other broadleaf weeds.

The discovery led Maurer to an important decision. He had to weigh the costs of implementing Plateau and Overdrive into his PGR portfolio against the benefits they could provide.

Using a new PGR mix that includes 2 oz. of Plateau for seed head suppression of fescue and 6 oz. of Overdrive for broadleaf weed control, Maurer has managed to save more than $11 per acre, freeing up resources to keep his program on track.

The eagerness with which Maurer adopted these new products demonstrates some of PennDOT’s secrets for success: their commitment to research and relentless pursuit of better vegetation management solutions.

Bare-ground makeover

In yet another example of PennDOT’s dedication to constant improvement, Maurer revamped his bare-ground program while adapting the PGR/broadleaf weed control program. His new bare-ground solution combines Plateau and Pendulum AquaCap herbicide from BASF, with Krovar and Oust Extra herbicide for bare-ground applications under guardrails closest to the roadway.

The bare-ground application is the first treatment of Maurer’s season. His crews apply a tank mix of 10 oz. of Plateau and 21/2 quarts of Pendulum AquaCap along with Krovar and Oust Extra at the end of April or beginning of May to keep these areas completely clear of vegetation.

“This bare-ground mix helps keep unwanted weeds and grasses from sprouting in guardrail areas,” Maurer said.

Along with the bare-ground application, the PennDOT team gets the PGR program started.

“We wait for the fescue grass height to peak just before seed head formation. If we hit it just right, we can expect the fescue to stay that height through the remainder of the summer,” Mauer said.

After the first PGR/broadleaf applications, crews go back to bare-ground applications in guardrail areas. Then herbicide crews begin a weed and brush control program on two-lane highways as well as low-volume basal and foliar herbicide applications for eradicating woody brush species encroaching into ROWs. When all that’s done, there’s not much time left for resting.