How to keep specialty crops safe from herbicide drift

Ohio’s corn and soybean growers could soon be spraying a lot more of two powerful herbicides on their fields.

That’s why agricultural experts from The Ohio State University are offering tips on how to keep those herbicides from getting onto other crops, especially valuable specialty crops such as grapes.

Doug Doohan and Roger Downer, both of Ohio State’s College of Food, Agricultural, and Environmental Sciences, are the authors of “Reducing 2,4-D and Dicamba Drift Risk to Fruits, Vegetables and Landscape Plants,” a new fact sheet that explains how herbicide sprays can drift onto nontarget fields, possible concerns about the herbicides 2,4-D and dicamba, and how to prevent unwanted damage to crops.

Doohan said the fact sheet is also intended to raise awareness of Ohio’s specialty crops, which include not just grapes but apples, berries, peaches, herbs, hops, pumpkins, tomatoes and nursery-grown trees, to name a few. Ohio’s grape and wine industry alone, according to recent figures, contributes some $786 million to the state’s economy.

“Creating and maintaining a heightened awareness of the specialty crop industry is probably the most important way to reduce the risk of future herbicide damage and the lawsuits that sometimes follow,” said Doohan, who’s a professor in the college’s Department of Horticulture and Crop Science. Downer is a research associate in the same department.

2,4-D and dicamba are the cornerstones of two new proposed weed control systems: Dow AgroSciences’ 2,4-D-based Enlist Weed Control System for genetically modified (GM) corn and soybeans and Monsanto’s dicamba-based Roundup Ready Xtend Crop System for GM soybeans.

Both systems were developed because more and more weeds have grown resistant to glyphosate alone. Glyphosate is the main ingredient in Roundup, for example, which is sprayed to kill weeds in widely grown Roundup Ready GM crops including corn and soybeans.

Both new systems are awaiting regulatory approval. But Doohan said both systems — and 2,4-D and dicamba as parts of them — are “likely to be used much more extensively and intensively throughout the Midwest, starting in the near future.” Included, he said, would be most of Ohio’s 4 million acres of soybeans.

The fact sheet is free at county offices of OSU Extension and at go.osu.edu/ReducingDriftRisk.