September 22, 2017
Arkansas is on the verge of banning the use, during the growing season, of a Monsanto-backed weedkiller that has been blamed for damaging millions of acres of crops in neighboring farms this year.
The weedkiller is called dicamba. It can be sprayed on soybeans and cotton that have been genetically modified to tolerate it. But not all farmers plant those new seeds. And across the Midwest, farmers that don’t use the herbicide are blaming their dicamba-spraying neighbors for widespread damage to their crops — and increasingly, to wild vegetation.
The issue has driven a wedge through farming communities in the Midwest, straining friendships and turning neighbors into adversaries.
Monsanto turned to dicamba because many weeds have evolved resistance to the company’s earlier weed-killing weapon of choice, glyphosate, also known as Roundup. Increasingly, Roundup no longer gets rid of farmers’ most troublesome weeds.
Dicamba is an old herbicide, but it’s now being used much more widely, in combination with a new generation of genetically modified, dicamba-tolerant crops. It’s also being widely used, for the first time, in the heat of summer, which makes the herbicide more prone to “volatilizing” — turning into a vapor and drifting in unpredictable directions.
This was the first year that farmers were allowed to spray it on soybean and cotton fields. (Some farmers did use dicamba illegally last year, provoking disputes between farmers that in one case, led to murder.) Many farmers embraced the new tool. But it quickly turned controversial: Farmers couldn’t seem to keep dicamba confined to their own fields.
The problem was worst in Arkansas, where almost 1,000 farmers filed formal complaints of damage caused by drifting dicamba. But the rogue weedkiller has hit fields across soybean-growing areas from Mississippi to Minnesota.
According to estimates compiled by weed scientist Kevin Bradley at the University of Missouri, at least 3 million acres of crops have seen some injury. Most are soybeans that aren’t resistant to dicamba, but vegetable crops like watermelons, fruit trees and wild vegetation have been injured as well. The dicamba vapors didn’t typically kill the plants but left behind curled leaves and sometimes stunted plants.
“There is no precedent for what we’ve seen this year,” says Bob Scott, a weed specialist with the University of Arkansas.