Cover Crops

(Kraig) In recent years we’re beginning to focus more on the soil moisture status and how these cover crops affect soil moisture. What we have going behind us is they’re installing neutron access tubes so we can measure the status of the soil moisture down to 9 or 10 feet and look at water extraction through the profile and we’ll continue that through the cover crop phase and up until we plant the sorghum. And the intent is to get a handle on what’s going on with soil moisture when we insert cover crops into a no till cropping system. Some hesitance arises in the use of cover crops relative to what’s the impact on my next crop? Will it use too much soil moisture? Crop yields so far have indicated that in this area, in this part of the state, it’s probably not an issue. But by installing these neutron access tubes we can get a better handle on exactly what’s going on with soil moisture. Below those cover crops and relative to say a fallow or a double crop soybean understand better if it’s the effect we’re seeing in either the sorghum phase, and sometimes we see effects even in the soybean and the wheat phase of the three-year rotation. If it’s due to nitrogen effects, nitrogen cycling and tie up in the residues, uptake and sequestration in those residues and subsequent release, or if it’s due to water dynamics. In a different study that would indicate some of these cover crops can extract water down to ten feet deep and those are the deep tap rooted brassicas, radishes and rapeseed for instance. By the same token with adequate rainfall over the winter and in the spring we saw minimal to no effect on the next year’s corn crop. And some of the research we’ve seen so far is that yes, you extract more water during the summer growing season but over the winter where you’ve had cover crops you’ve got more residue. And we make up a lot of that during that winter and early spring season, especially going ahead of sorghum. And so the net result has so far been either neutral or positive. And long term we hope to build soil structure, soil organic matter and all the other benefits that you achieve with cover crops.

No Comments Yet.

Leave a reply

You must be logged in to post a comment.