Each spring, far too many farmers gaze across their fall-tilled soybean fields and see gullies and rills carved into the slopes.

This scenario is confirmed by data collected by the Illinois Department of Agriculture, which shows approximately 25% of the cropland fields throughout Illinois are experiencing significant ephemeral and gully erosion the past 5 years.

Unfortunately, fall tillage after soybean harvest is leading to excessive soil erosion, reports Bob Frazee, University of Illinois Natural Resources Educator. Many of the sloping fields where soybeans have been grown are showing severe erosion problems, especially after this season's heavy rains.

For the least amount of erosion, U of I agronomists recommend not tilling soybean stubble in the fall. According to experiment station data, the following season's corn yields are unaffected by either performing fall tillage or leaving soybean stubble untouched.

Leaving the soybean crop residue untouched on the soil surface throughout the fall and winter months provides valuable soil protection. Plus, eliminating this unnecessary fall tillage trip can cut crop production expenses and result in more profit.

Soil erosion is usually a more serious problem after a soybean crop than after corn. According to Frazee, one reason is the soybean plant's root system is not nearly as extensive as that of the corn plant. The most important reason, though, is that soybeans produce considerably less vegetative growth in terms of stalk and leaf material than does a corn crop. Consequently, this results in much less crop residue after harvest to be available to protect the soil from erosion.

Frazee reports that Illinois farmers are rapidly adopting the "Don't Touch Soybean Crop Residue" philosophy. Recent studies show that anywhere from 60% to 75% of soybean fields are now being left untilled following fall soybean harvest.