Soybean growers need to look at the big picture when they’re considering whether to spend money on cover crop seed and planting to help protect their soils from wind and water erosion during the winter and spring.
Example: A three-year University of Arkansas System Division of Agriculture study on the partial returns from planting cover crops shows the tillage costs in conventional soybeans can run up to $30 an acre – or more than the cost of most cover crop seed.
“If we shift to a generic cover crop treatment, you have to understand we’re taking tillage out of that rotation because when we implement cover crops we can only truly realize their full benefit when we also implement no-till practices,” said Trent Roberts, Extension soil fertility specialist with the University of Arkansas.
“When you think about that, yes, we’re adding the cost of cover crop seed to that production system, but we’re also removing tillage from the equation, and one thing we’ve found is that in a traditional soybean production system the cost of that tillage – the labor, the fuel – can equate to about $30 an acre.”
Roberts, a speaker at the University of Arkansas’ virtual Rice and Soybean Field Day, said that $30 an acre is a “significant cost that will often more than pay for cover crop seed, planting and at least a portion of the termination cost.”
University researchers conducted a partial returns analysis, looking at variable input costs for the cover crop, fallow and double-cropped wheat and soybeans treatments in the study at the Pine Tree, Rohwer and Vegetable Research Stations in Arkansas.
“With the fallow treatment we obviously have full tillage, but we’re only going to have a single burndown for any winter weeds that may occur,” he noted. “But one difference with the fallow treatment is we don’t have any winter cover crop seed costs. Those can be offset by removing tillage from the system.”
The agronomists also looked at a soybean-wheat double-crop system although farmers appear to be moving away from the practice because of the potential for reduced soybean yields from late planting.
“There’s a significant amount of cost in the double-crop system because we have the wheat-for-grain seed, which is typically higher than cover crop seed; in-season herbicide weed control for the wheat crop; additional fertilizer for the wheat crop; and an added planting pass,” he said. “But we also have the revenue from the wheat crop to help offset some of those increased wheat input costs.”
The highest partial returns in the study were seen from the majority of the cover crop treatments, Roberts noted. “But they were also very high in our wheat double-crop systems. There were no statistical differences in the partial returns of our double-crop systems compared to some of our higher yielding cover crop treatments.
“The message I’m trying to relay there is a wheat double-crop system can be profitable. You will lose yield in your soybean due to the late planting, but, oftentimes, the value of the wheat will make up for any potential yield loss we see in the soybeans.”