Crop residue left on the surface shields the soil from rain and wind until emerging plants provide a protective canopy. Crop residue also improves soil tilth, adds organic matter to the soil, and may even result in a little grain being left for wildlife. Less tillage reduces soil compaction and saves the farmer time and fuel.
Three types of crop residue management systems are common:
Mulch-till uses such implements as a chisel plow or disk to till the entire field.
No-till leaves the soil and crop residue undisturbed except for the crop row where the seed is placed in the ground.
Zone or strip-till uses coulters to till a 5"-7" strip for injecting starter fertilizer and planting in one operation.
How it helps...
Ground cover prevents soil erosion and protects water quality
Residue improves soil tilth and adds organic matter to the soil as it decomposes
Fewer trips and less tillage reduces compaction
Time, energy and labor savings are possible with fewer tillage trips
Plan for residue levels needed to reduce erosion. Planning for residue cover begins at harvest. Reduce the number of tillage passes and set tillage tools to shallower levels to leave more residue on the surface.
Straight points and sweeps on chisel plows leave more residue than twisted points.
Consider your soils and crop rotation. Heavy residue (corn, for example) on droughty soils can help conserve soil moisture; however, heavy residue on poorly drained soils can delay spring warming and drying.
Nutrient and pest management practices might need to change as you farm with higher levels of residue.
You may need different equipment suited to the type of crop residue management you plan to use.
Measure crop residue using the “knotted line” method. Divide a line into 100 equal parts and stretch it diagonally across the crop rows. Walk along the line counting the number of marks that have residue under them. The total number of marks with residue under them is the percent cover for the field. Take three to five measurements in representative parts of the field.