"There is no tolerance. If even one grain of the treated seed shows up in a truckload or storage bin in the fall, the entire lot is considered contaminated and cannot be used in food for humans or animals," says Mark McCloskey, who oversees compliance for the Bureau of Agrichemical Management in the Wisconsin Department of Agriculture, Trade and Consumer Protection. "We have no choice but to condemn the entire load, at the farmer's expense. If we find any treated seed in elevators, we would have to condemn the entire bin."
Seeds treated with insecticides and fungicides are commonly used by farmers to protect seedlings at planting. These seeds are dyed bright colors to differentiate them from untreated seeds.
Greg Helmbrecht, the department's seed specialist, offers this advice to farmers who plant treated seed:
After hauling or planting treated seed, use a pressure washer to clean all equipment, including gravity boxes, truck beds and wagons. Then visually inspect it, looking for any of the brightly colored seeds.
Check with your supplier about returning or disposing of any unused treated seed. If you are going to store it, keep it separate from grain, forage and feed storage areas. Secure it so that birds and other animals cannot get into it.