However, loss of the OP insecticides would have a large economic impact on several major crops, including alfalfa, cotton, and wheat. Loss of carbamate insecticides would have a major economic impact on cotton, rice, and sorghum. The 1998 Missouri Corn Crop Performance data is now available on the web. The books are also available. Contact your local University Extension Center.
Supplies are limited.
There are a number of considerations. Soybeans are typically planted later than corn allowing more problem weeds to emerge and emerge faster. Soybeans can tolerate 4 to 6 weeks of weed competition while corn is more susceptible to early season competition. Soybeans form a more complete canopy of leaves than corn and can be planted in narrow rows or drilled giving faster canopying to shade weeds. Young soybeans are more resilient than corn to damage occurring during post emergence herbicide applications.