Agronomy Library > Soil Conservation

Basics of Residue Management
Author: Reduced Tillage LINKAGES
Date Created: March 26, 2002
Last Reviewed: February 15, 2007

Plant residues are a precious resource in reduced tillage, providing enrichment of soil organic matter, moisture and physical characteristics, microhabitats for crop seedlings, and reduced weed germination. 

Good residue management exploits these benefits: 

•  Fit the combine-harvester with a straw/chaff spreader
•  Spread straw and chaff evenly
•  Harrow the straw in the fall or spring before seeding 

The key to harrowing straw:
•  Speed of the tractor-sufficient to spread the straw evenly without bunching
•  Timing-spring generally, or fall depending on the specific situation
•  Dry soils provide better medium for straw handling 

Factors that affect residue management:
•  Crop type-heavy crops providing more straw are a positive factor
•  Width of cut-affects the spread pattern; aim for an even spread
•  Stubble height-tall stubble or alternate height stubble increases moisture retention and snow trapping
•  Straight cut vs. swathed-straight cut may give higher stubble; swath may give more straw
•  Straw quantity-some crops produce more straw than others; canola mustard, short vine pea and lentils produce less straw and it tends to break down easily
•  Conventional vs. rotary combine-rotary produces shorter straw and may not require chopping
•  Straw choppers and spreaders-under high yield wide swath conditions, original equipment choppers and spreaders are often inadequate
•  Chaff spreaders-chaff spreading is essential 

Farmer experience: (4 farmers share their experiences)
•  Farmer A uses a 50 ft Flexi-Coil heavy harrow with a 360 hp tractor in the spring. According to this farmer, fall harrowing creates problems at seeding.
•  Farmer B bales the straw, which he takes to a feedlot, and stubble grazes livestock.
•  Farmer C uses an air blowing system on the combine to spread the chaff.
•  Farmer D blows the chaff into a high dump silage wagon trailing behind the combine