By Ken Panchuk, PAg, Provincial Specialist, Soils
Fine chopping and uniform spreading of straw and chaff is a critical first step in zero-till or min-till seeding systems. This allows for ease of seeding in the next crop and also improves soil moisture conservation.
Fine-cut straw choppers are now the standard in the industry, allowing the finely chopped straw and chaff to be spread uniformly over the width of the cut. These high-performance choppers also require regular maintenance to effectively handle a variety of crop types under variable harvest conditions. Servicing the flails and knives prior to harvest assures that the straw chopper will do the job effectively and efficiently and without down-time during harvest. This is particularly important for more difficult-to-chop residues like flax.
Producers have other options for managing crop residues, such as use of straight cutting headers or stripper-headers to leave the stubble as tall as possible. If moisture conservation in drier areas is the focus, then the stubble is left standing to catch snow and conserve moisture. Tall-stubble technology that involves seeding between the rows of standing stubble will further help conserve moisture for the next crop.
If fields have very high residue amounts, consider a “residue manager with fixed knives,” which is a specially designed type of rotary mower that can finely chop and shred heavy residues. The residue manager can be used late in the fall or early spring, providing flexibility in leaving the stubble standing to catch snow or, if the soil is recharged with moisture, to shred the residue in fall to reduce snow trapping. Also, the use of the residue manager leaves the stubble roots anchored to prevent soil erosion.
Some crop residues need just a little more spreading, which can be accomplished by heavy harrowing during a dry day to help distribute the chopped straw.