Less tillage has enabled Jacobs Farms farmer Ryan Speer, Halstead, Kan., to get by with two 200-hp. tractors. It has also reduced herbicide use, strengthened yields and improved erosion control.

Soybean yields have increased by 15-20% following a cover crop compared to straight no-till beans without cover crops. Cover crops join the rotation whenever the weather allows. The rotation is two years corn, soybeans, double-crop wheat, double-crop beans, then back to two years of corn (five crops in four years with multiple cover crops between cash crops). Rye and radishes always follow the second-year corn before beans, Speer says.

Although no-till is a no-brainer on the 4,000-acre High Plains dryland and irrigated operation, the certified crop advisor is also in demand as a speaker on cover crops.

“I used to think that cover crops were just one more chore we did not need until our wheat crop froze in 2007 on a particularly terrible sandy field,” Speer says. “We replanted into freeze-killed residue and had a 25-bu. soybean yield increase from that thick vegetation using 35% less irrigation water and only one glyphosate spray instead of three. The groundcover crowded out the weeds. Now, the cereal-rye, radishes and other cover-crop mixes retain our spring rains through the dry summer season and control evaporation, sustaining our soybeans longer. Our sandy soils can only hold 1-1.25 in. moisture per foot of soil profile, so the cover crops store spring rains through the summer for us while reducing evaporation.”

Two years of extensive replicated strip trials have fine-tuned cover crop mixtures; often rye and radish mixes before soybeans. “The cover crops also definitely help reduce chemical costs by crowding out the weeds, too.”