I recently spoke at the Southwestern Wisconsin No-Till Field Day, where we’ve had an extremely wet spring. One recent storm in this area dumped more than 10 inches of rain in 1 day.
There was tons of soil loss and erosion on traditional and conservation-tillage fields in that area. But in no-tilled fields, I noticed the extreme weather was handled very well.
Probably the most important reason these no-tilled fields survived the storms without erosion was because of their high residue levels.
We visited two farms on this field day and they were both no-tilled, although farmers at both sites handled their residue a little bit differently.
On one farm, vertical tillage and chopping corn heads are used. On the other farm, only moderately aggressive knife rolls are used.
Both farms had excellent stands and no erosion rills in the fields, but the farm where vertical tillage and chopping corn head was used seemed to have a bit more soil movement.
The question of the day at the field day was, “How should we manage residue in a no-till corn and soybean rotation?”
To answer this question, one must first understand that with no-tilled systems, residue is the key to reducing soil erosion and it’s our principle source of carbon to build organic matter in soils.
Residue protects the soil from rain impact and can increase the soil’s water-holding capacity dramatically.
Crop residue and roots bind the soil. Crop rows act as mini terraces that slow down water…