Some dig deep to identify the yield robbers on their farms. Jules Willott only had to dig 3 inches.

After years of letting his fertilizer rep take his soil samples, the Mexico, Mo., no-tiller decided to do the job himself. What he discovered as he dug his soil samples was a shallow compaction layer.

“There was good, loose soil for 3 inches, then a 1.5-inch layer that was hard and then good soil below that,” Willott observed. “Our roots were getting through, but I think it must have slowed them down a little.”

The 15-year no-till veteran wasn’t convinced it was compacted enough to hurt yields on his soybean, wheat, clover and milo crops, but it was on his mind. When bad weather kept him from planting a crop in 2009, he decided to seize the opportunity to experiment with some compaction-alleviating cover crops.

Montgomery City, Mo., regional extension specialist Richard Hoormann was more than happy to help. He’d been looking for opportunities to see how cover crops that had been successful in other regions would perform locally.

Together, they broadcast-seeded two timings of nine different cover crops on Willott’s challenging claypan soils. Wheat, purple-top turnips, oil radishes, tillage radishes, annual ryegrass, Austrian winter peas, rape and other turnip varieties were planted in 22-by-125-foot plots.

Diverse Benefits

 The cover crops were planted from August through October. They grew, winter killed and then Willott no-till drilled soybeans into the plots in spring of 2010.

Wet conditions in the fall of 2009…