July 2017


Keeping the traffic flowing in Sacramento County

Sacramento County encompasses 994 square miles that extend from the low delta lands between the Sacramento and San Joaquin rivers north to roughly 10 miles beyond the state capitol and east to the foothills of the Sierra Nevada mountains. It runs through the middle of the 400-milelong Central Valley, which is California’s prime agricultural region, producing everything from grapes to corn.

And it’s this rich agricultural region that produced a new tool, Cleantraxx™ herbicide, for roadside managers to use in controlling tough weeds. It is important because passable roads are needed to transport the county’s almost 2 million people to work, school and countless other destinations.

Making sure motorists get there safely is the job of the County of Sacramento Department of Transportation (SACDOT). It manages the majority of roads and roadsides throughout the diverse areas of the unincorporated Sacramento County; the only exception being major highways, which fall under the jurisdiction of the State Department of Transportation, called Caltrans.

Brian Walsh is the tree and landscape highway maintenance supervisor for SACDOT. He oversees six employees who are responsible for the mowing and chemical treatments used to maintain the roads in Sacramento County.

SACDOTinset Like many roadside managers, he’s contending with a number of issues at any given time, including landowners’ concerns in residential and urban areas, budget concerns and encroaching weeds that are becoming more and more difficult to control. The geographical diversity and agricultural nature of Sacramento County presents additional challenges to Walsh and his team, seemingly around every bend in the road.

“Beyond all the residential and urban areas, we need to be extra careful when treating near areas of agriculture, especially with so many sensitive crops,” says Walsh. Walsh and his team allocate the majority of SACDOT resources on approximately 1,000 miles of the most-used county roadsides in an effort to maximize their impact.

“There’re a lot of miles that realistically we just aren’t able to touch on a regular basis,” says Walsh. One way he’s working to stretch his vegetation management program budget is using herbicide treatments instead of mechanical. “We try to integrate herbicides into our management program rather than more mechanical treatments,” says Walsh. “We’d like to continue to do more herbicide spraying to maintain the roadsides, because we can maintain more miles that way.”

From nut trees to roadsides
An important agricultural presence in Sacramento County is the tree nut business. Weed control among these sensitive crops was made a lot easier with the recent introduction of Pindar® GT herbicide. Offering consistent residual control of tough weeds, while at the same time providing excellent crop safety, has made it a mainstay in this business.

“Here in California, many of the tree nut producers have been using a great herbicide called Pindar GT for years,” says Walsh. “We always wanted to use it on our roadsides because we saw the results it provided on tough weeds like marestail, but without damaging those sensitive trees, which we also need to be careful around.”

Walsh and others got their wish when Dow AgroSciences applied for and received label approval for Pindar GT to be used on roadsides and other use sites under the brand name Cleantraxx™ herbicide. And because it was already in use in California, it already passed the stringent criteria set forth for a herbicide to be considered for use by county and state transportation departments.

SACDOTinset2 “The fact that it carried a Caution signal word made it attractive because that makes it a fit within our established guidelines for herbicide use,” says Walsh. “When Dow AgroSciences gained label approval for use of Cleantraxx on roadsides, we couldn’t wait to get it out on our roadsides, and started putting it out in 2015.”

Besides glyphosate-resistant marestail, the newly branded Cleantraxx is labeled to control 65 broadleaf weeds and annual grasses. As a tank-mix partner, it’s suited for selective weeding within roadside applications, as well as in bareground situations.

The county has two 1,000-gallon injector spray trucks, as well as a 300-gallon conventional spray truck, to make the majority of its herbicide applications. Applicators had been having regular clogging issues with herbicides.

“Right away, we noticed that Cleantraxx, as a liquid formulation, works much better in our spray rigs,” says Walsh. “The old products we had been using, many of which were dry formulations, would clog up our injection system. But, our rep from Dow, Beau Miller, helped us work with this formulation to make sure that wasn’t happening anymore.”

More control — even on the toughest weeds
A majority of the herbicide treatments center on asphalt center islands and maintaining a 6- to 8-foot clean shoulder along roadsides. Cleantraxx™ herbicide is tank-mixed with glyphosate, and treatments typically go out in November.

“The Cleantraxx and glyphosate mix has provided great results,” says Walsh. “We’ve had less weed escape, resulting in fewer resprays.”

Some of the species on the radar are filaree, willow-herb and marestail.

“Marestail is particularly challenging because it will emerge in the fall and sit there all winter and grow a taproot,” says Walsh. “Cleantraxx offers us postemergence control of marestail. Others can provide preemergence control, but not post. It just seems to provide more knockdown and long-term control than other herbicides we’ve used on it.”

The dual-action formulation of Cleantraxx offers both preemergence and early postemergence control of broadleaf weeds and annual grasses. This allows more flexibility for roadside managers and applicators, as ideal spraying conditions can vary throughout the season and a window for a preemergence herbicide may be narrower.

“We also like introducing new modes of action into our herbicide program, as it helps work against weed resistance issues,” says Walsh.

Methodical approach pays dividends
Another, newer herbicide proving to be a workhorse for SACDOT is Capstone® specialty herbicide. “We use Capstone at the end of summer to clean up some of the really hard-to-control stuff like poison oak and stinkwort, which is a really challenging weed for us,” says Walsh. “The residual control it provides buys us time and makes things more consistent.”

Although the results have been good with Cleantraxx and Capstone, Walsh and his team did their homework before making the first application.

“I’ve always tended to be methodical and cautious when using herbicides,” says Walsh. “But Beau has done a great job in helping train our guys with these new herbicides, and the results are that the roads look much better now than when we took over.”