Wheat harvest season is well underway for many U.S. wheat growers. Some of the first soft-red wheat harvested by U.S. farmers in 2015 is the worst in at least 17 years, according to Bloomberg and other sources.

This year’s heavy rainfalls  – up to three times the normal amount – have made mycotoxin diseases like vomitoxin more prominent in many wheat-growing states.

USDA scouts recently noted that “there have been reports of elevators rejecting wheat loads due to the presence of vomitoxin,” a toxic fungal residue, also known as Deoxynialenol or DON. “Winter wheat left unharvested continues to have quality issues, including problems with scab, sprouting and mold,” the scouts added. In Michigan, official scouts said that “intermittent rain showers limited the amount of winter wheat harvested this week – moisture levels were reported as high, and some growers reported vomitoxin issues.” And in Ohio, USDA staff said that “some wheat has been of such poor quality, it is not able to be sold.”

Soft-red winter wheat is typically sold to mills and turned into flour, which is then used to make consumer products like crackers and cookies. However, the poor quality of this year’s winter wheat harvest means that it may only consumable in animal feed. According to the USDA Risk Management Agency, high levels of vomitoxin may result in either a discount in price or the requirement to destroy the grain.

So how can you avoid contamination in your crops? There is no sure DON prevention, as environmental conditions play a big part. However, there are several good practices for controlling it such as crop rotation, choosing a variety with some resistance, applying fungicides in a timely manner and tillage practices. Iowa State University engineer Charles Hurburgh warns that storing wet grain, even overnight and especially without aeration, shortens its life considerably. You should check it weekly, monitoring for spikes in the temperature, and test it regularly for evidence of DON or other mycotoxins.