Do Cover Crops Use Too Much Moisture?
Seventeen years ago, before Green Cover began as a small, on-farm business, Keith and Brian Berns had to find the answer to an important question, “will cover crops use up all of my moisture?” The brothers were interested in cover cropping because they knew they were losing top soil to wind erosion on their family’s farm in Nebraska. But they were not willing to grow a cover crop if it meant robbing their cash crop of crucial moisture. Following an experiment they heard about from Gabe Brown, Keith and Brian set out to test moisture usage of different cover crop species to really understand just how much moisture they needed to grow.
Putting Cover Crops to the Test
After receiving a SARE grant, the brothers set up moisture sensing equipment in 18 different plots after wheat harvest. 15 of these strips were single species, 3 of them were cover crop mixes and they also monitored wheat stubble on its own as a control. Sensors were placed at 1ft, 2ft and 3ft depths to measure just how much moisture was being pulled from the soil profile.
Their biggest takeaway? Cover crop mixes are far more efficient at using moisture than single species monocultures.
Their findings were validated by the studies done on Gabe Brown's farm. In a very dry year where only an inch of rainfall was received during experimentation, Gabe's experiments demonstrated that cover crop mixes use water much more efficiently and can produce a lot of biomass with minimal rainfall.
Then for Brian and Keith's experiments which took place in a relatively wet year, they observed that the rainfall received actually replaced the moisture used by the cover crop mix at the end of the experiment.
You can learn more about these experiments, see data and additional photos in this short video where Keith describes their methodology and their findings.
Manage Your Moisture
When it comes to planting a cover crop in a very dry year, knowing the best time to terminate is crucial for optimal moisture management. Check out this article to learn more about managing your cover crop for optimal moisture usage in both wet and dry conditions.
If you'd like to talk through your goals and context when it comes to planting a cover crop mix this summer or fall, give our team a call at 402-469-6784 or head to our website to shop our pre-made mixes.
