There is an effort underway to minimize glyphosate use before bud break in grapes. It doesn’t need to be used all the time. A lot of annual weeds can be controlled with several herbicides. Keep the glyphosate for hard to control perennials.
John Roncoroni, a UC Cooperative Extension Weed Science Farm Advisor in Napa County, has made strides toward meeting this challenge. “Many times, growers will do two applications of herbicides during the year … but what I’m trying to do is push it back to post-leaf fall after the season to clean up and come back with a pre-emergent material right before bud break then maybe skip that last glyphosate treatment after bud break.”
Roncoroni explained that the idea is for grower not to use glyphosate on weeds during the growing season.
Roncoroni mentioned that he works with school districts and municipalities, and there are many of them want to ban the use of glyphosate.
“It’s not so much the glyphosate molecule; it’s that we have all used so much of it over the years,” he said. “Rely on preemergent materials early in the season and reserve glyphosate as a clean up at the end of the season.”
“My philosophy when I talk to people is to not ban it but to save it for needed use. Maybe we pretend that there are no herbicide alternatives available. We have annual grasses that are easy to kill, then use an alternative herbicide for that. But when you have weeds where you need that systemic benefit of glyphosate, then use it. It is a good molecule, and it has an important fit in weed control, but it does need to be used all the time,” Roncoroni said.
And of course, reading and following the herbicide label will maintain its safety.
The California Weed Science Society (CWSS) held their annual meeting in Sacramento from January 13-15, 2016. The meeting fostered collaboration between Pest Control Advisors (PCAs) and farmers as they gathered to learn the newest innovations in weed science.
John Roncoroni, weed science farm advisor for the UC Cooperative Extension in Napa County, as well as the outgoing CWSS president, said four Fresno State students gave presentations at the meeting on their research. “We’ve had really great student participation—the amount of student scholarships we’ve given is up this year, the posters, the students and our attendance this year is up,” Roncoroni said. Pre-registration was about 530 people.
Roncoroni suspects that rain pushed people to attend, “because—with that rain—we’re looking at more weeds this year. So people are looking for the newest information on weeds. This year’s conference really has done a really good job of putting that information together. Kate Walker, our program chair, has really done a fine job of putting together a great program.”
Kate Walker, technical service representative for BASF Corporation, is also the new, incoming CWSS president.
The CWSS recently updated its published textbook, Principles of Weed Control, 4th Edition, that focuses on the applied aspects of weed control. The purpose of this textbook is to provide access to the fundamental principles and concepts of weed management in California. The book is designed for use at the college level by students who have an interest in pursuing a plant science or associated background of course work. It is also a useful resource for individuals studying to become PCAs and applicators or for consultants who work in weed science. For more information, go to the CWSS website Publications page.