No-Till Farming: Residue Management Considerations
Posted by: Todd Kamp on Feb 2, 2018 5:00:00 AM
Conservation benefits provided by no-till farming are well documented. Yet, challenges exist. For example, crop residue of some type gets distributed at harvest, and conservationists agree that this practice of leaving a certain amount of residue in the field is good for the soil.
However, leaving residue on top of no-till systems may create a mat of material that can be tough to cut through come no-till planting season. Plus, it can also lower soil temperatures, which some studies show to reduce yield. Plus, in general, residue does need to have its breakdown optimized to boost the nurturing of soil nutrients.
So, the question is, what crop residue management considerations should farmers understand in no-till situations?
First, it’s important to dispel any fictional beliefs regarding residue management. According to Professor Mahdi Al-Kaisi in his Iowa State University Extension article Myths and Facts about Residue Breakdown, decomposition is controlled by certain biological and enzymatic processes controlled by microorganisms and influenced by other factors.
That is, his studies state that tilling under the residue, or adding nitrogen on top of it, does not speed up the decompositon process. Other popular ag publications and noted university studies support this conclusion.
Yet, his work in this field of study does reiterate that crop residue is indeed one of the most important conservation tillage factors for improving a soil’s physical and chemical properties. Also, harvest has a considerable impact on crop residue distribution and management.
Of course, that means proper residue managenent is critical. Paul Jasa, Extension Research Engineeer with the Univeristy of Nebraska agrees. Here are some key points paraphrased from his Cropwatch article, Recommendations for Managing Corn Residue at Harvest:
To aid decomposition, getting the stalks broken open and down to the soil exposes them more to microbes and weather conditions that will help speed decomposition. With disease control built into some hybrids, decomposition can be slowed, so processing the stalks with the cornhead is even more important as there is less natural breakdown.
Realize, less processing catches more snowfall which is good for moisture retention, but it doesn’t allow the stalks to decompose much before planting. However, over processing may lead to residue getting blown around the field.
Proper residue management at harvest is key to preparing for the next crop, and it can also make conservation tillage farming and no-till corn planting easier.
Harvesting equipment can make a difference in how effectively residue is processed. Two examples of how corn headers assist in stalk breakdown are shared here – one by a farmer from the midwest, and another by a dealer from Canada:
“The stalks are all processed right in front of you – all cut into the size you want. And with the decomposition of the stalks the way they are processed, the Geringhoff Rota Disc has definitely helped my corn yields.”
—Duane Hinchley, Hinchley Dairy Farms, Cambridge Wisc.
“Since we are usually harvesting corn late in the fall, we don’t have a lot of warm weather to help with working the ground or managing the residue. With the cooler weather, the residue doesn’t break down as fast, so the more we can do to break it up, the better off we are.”
—Todd Botterill, Botterill Sales, Newton, Manitoba
Proper crop residue management is indeed a critical factor for bettering the properties that define a soil’s profile – reducing runoff, retaining mositure, boosting organic matter and microorganisms, and maintaining good soil structure.
Harvest equipment solutions that shred and distribute residue evenly can help support that cause in no-till systems where corn planting and conservation challenges are unique.