Ask an Agronomist
Can Tillage Practices Reduce Organic Matter in Wheat Ground?
Nov 13, 2012
Question: I have been 100% no-till in my farming operation for 26 years. I am wondering if spreading wheat and using shallow vertical tillage to incorporate will lessen organic matter; which in return over a period of time will reduce crop yields? My thinking is any time you bring soil to the surface enabling contact from the sun you are destroying a percentage of organic matter, if you believe my thoughts to be correct, can you please give me your opinion on how much damage to soil structure you feel is occurring from shallow vertical tillage?
Answer: I'm not sure what region you farm in, and that will have a big impact on the relevance of my response. When I first moved from England to Kentucky 23 years ago, I began working with about 25 growers. My primary responsibility was to help them increase their yields and profits by introducing some of the European crop management practices which had helped some of the western European growers reach or exceed 200-bushel-per-acre wheat yields.
Initially, many of these growers were broadcasting wheat with spinner trucks and working it in with a disc or field cultivator. The standards of emergence, uniformity and plant populations across their fields were entirely too variable for maximum yields, so an important step the following year was to talk all of these clients into buying new or well-maintained, older model drills. This turned out to be a good strategy, as their stands improved and yields quickly climbed.
Based upon these and other experiences across the United States, and depending on the number of acres you expect to plant on a regular basis, I would strongly encourage you to buy or rent a good, well-maintained, no-till drill. The operating costs per acre will be similar as running a vertical tillage tool, but I think your stands will be more consistent and the soil disturbance will be reduced. I also believe with the improved seed placement provided by the drill, you could lower your seeding rates between 10% and 20%, compared to broadcasting seed, to save money.
I don't have any data to suggest how much damage you’re doing to organic matter by cultivating the soil with vertical tillage, but I can tell you that most of my growers are making +/- twice the yields they were 20+ years ago, and by using no-till their soil quality and organic matter is increasing slowly.
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