The problem has reached a fever pitch in the Bootheel, where more than 100 complaints of drift have been reported since late June — exceeding the Department of Agriculture’s usual statewide caseload for an entire year. Kevin Bradley, a professor of plant sciences at the University of Missouri and a lead agricultural extension scientist, said that everything he’s seen suggests dicamba is responsible for crop damage on farms across the area, though he has not observed Bader’s case firsthand.

Bader’s farm, in Campbell, Mo. — situated in rolling hills just west of the Bootheel’s level expanses of soybeans, rice, corn and cotton — is Missouri’s largest producer of peaches, accounting for more than half of the state’s harvest. But even with much of this year’s crop still to be picked, Bader is bracing for production to take a dramatic hit.

He says the farm’s typical harvest of 5 million to 6 million pounds may be reduced by 40 percent this year, as trees with withered or missing leaves have borne smaller fruit. Bader reports that almost 10,000 other trees mustered only walnut-sized peaches not even worth picking. He says the shortfall will amount to a loss of produce of $1.5 million to $2 million.