Wednesday is the final day for corn growers to submit comments to the government about the use of the herbicide atrazine.
The Environmental Protection Agency has proposed regulation to reduce the allowable levels.
According to the National Corn Growers Association, those limits are essentially a ban on atrazine.
NCGA says it is a key component to fight some of the toughest weeds.
In addition to its use in corn, atrazine is also used by sorghum and sugar cane growers.