A recent question came to us:
We are curious about the use of cover crops to remediate compaction as compared to traditional methods of “heavy iron”.
Here’s some background:
Researchers at the University of Missouri have been using annual ryegrass on their claypan soils. These only have 2-3″ of topsoil and then very thick claypan layer. Newell Kitchen KitchenN@missouri.edu is in charge of this research project and Matt Volkmann volkmannm@missouri.edu is technician is charge.
Here’s a response from them on their research results to date:
“Without a doubt the soil in the (field using annual ryegrass as a cover crop) is building structure and showing evidence of an increase in living organisms. During harvest, Newell took opportunity to dig a spade full of dirt from both that field as well as one of the plots with no cover crop and minimal till. The sampling was only 60 yards apart from each other and represented identical landscapes which were located an equal distance from a natural summit in the landscape. A spade-full from the field with annual ryegrass contained 16 different worms, lots of root hyphae and would be characterized as having a platy structure. A spade-full from the comparable plot nearby, with no cover crop, only had two worms, no worm channels to speak of, no fibrous root system and minimal structure.”
These results are consistent to those experienced in southern Illinois and Indiana, where fragipan soils have traditionally prevented corn roots from penetrating into deeper soil where moisture and added nutrients reside. Reaching those lower layers is a recipe for bigger yields, especially in dry years.
Tags: all cover crops, Annual ryegrass, cover crop research, deep rooting, Matt Volkmann, Newell Kitchen, nitrogen-friendly cover crop help reduce the cost for fertilizer., No-Till, soil compaction, University of Missouri
Leave a Reply