Lessons Learned: Cover Crops Provide a Grand Bargain and Return on Investment

Source: Oregon Tilth
Format: Lessons Learned

A column for organic practitioners that promotes knowledge-sharing, education and strategies of what works in organic production.

By Chris Roddy & Samantha Tellatin


Imagine the sleek, high-backed chair of a powerful stockbroker in a field of recently harvested brassicas. It looks and feels weird, right?

However, farmers take part in their own high-stakes financial drama. Only instead of at a fancy conference room, it might take place in the high perch of a tractor or over dinner at the kitchen table.

It’s a never-ending game of balancing financial conflicts. Invest resources and time to maximize a farmland’s long-term returns but still meet the need for a productive now. Land management decisions that build productivity and value for the future are requirements for sustained success.

Cover crops don’t scream “sexy investment opportunity” in a farm enterprise budget. Yet it’s unwise to underestimate the profitability of these beneficial legumes and grasses.

The question is: What economic returns can be expected from planting cover crops?

Think of it this way. It is easy to understand how good soil health—much like good health in people—can provide economic benefits and prevent costs in comparison with depleted, ailing soil.

Cover crops can act as an “apple a day” doctrine for many farms, increasing soil health and protecting long-term productivity. Simple enough. Still, it’s hard to project and monetize a farm’s fecundity a decade from now. In addition, most research on cover crops is generalized. A wide variation in landscape types and production systems means there are few cut-and-paste cover crop models with known economic benefits for growers across the country.Nonetheless, here are a few economic arguments for investing in cover crop practices.

ARGUMENT 1: COVER CROPS INCREASE CROP YIELDS

It’s the basic (math) goal for most farmers: higher crop yields mean more product to sell.

The Conservation Technology Information Center and Sustainable Agriculture Research and Education Program (SARE) have collected annual crop yield data, since the 2012–2013 harvest year, from farmers using cover crops. The survey, focused on corn and soybeans planted after a cover crop application, shows consistent yield increases every year. Corn yield increases ranged from 1.9 percent to 9.6 percent while soybean yields increased from 2.8 percent to 11.6 percent. Using 2016 National Agricultural Statistics Service averages for soybean crop prices and yields, an increase of 2.8 percent would mean collecting $14.80 more per acre harvested. An 11.6 percent increase would drive revenue up an additional $56.72 per acre.

production cost

ARGUMENT 2: COVER CROPS INCREASE (AND DECREASE) OTHER IMPORTANT STUFF

Crop yield increase from the use of cover crops isn’t just about fertility enhancement, although it is the most visible economic benefit. Rather, higher crop yield is attributable to a long list of health and wellness benefits that cover crops provide for soil:

COVER CROPS BUILD SOIL BULK AND STRENGTH
Terminated cover crops add much needed organic matter to build and maintain soil. Rainfall and irrigation infiltration rates increase with a healthier (and “beefier”) soil structure. More water is absorbed, and it sticks around for longer periods of time, decreasing irrigation frequency. Indiana farmer and SARE Cover Crop Innovator Dan DeSutter reported an average benefit of $30 per acre, just from increasing soil organic matter with cover crops.

COVER CROPS KEEP SOIL IN PLACE

Erosion is a costly event on farms, diminishing a farm’s land value by as much as 7 percent. Prior to termination, cover crop roots hold soil in place, retaining organic matter often lost from rain and wind erosion. They act as a shield and anchor, providing stability for land under constant punishment from heavy rains and winds. Studies have shown that cover crops can reduce soil loss caused by erosion. In the Great Plains, use of spring peas as a cover crop cut erosion by as much as 69 percent. In California, using mustard as a cover crop helped lower erosion by 82 percent.

COVER CROPS ADD FERTILITY

Cover crops’ ability to add nutrients to soil, most notably nitrogen, decreases dependency on fertilizers and other inputs. In addition, cover crops help “scavenge” and hold onto nitrogen already in the soil, preventing runoff or leaching into groundwater. In Georgia, legume cover crops (winter pea, hairy vetch, crimson clover and berseem clover) were found to replace 27 to 176 kilograms of nitrogen per hectare.

COVER CROPS PREVENT PESTS AND WEEDS

Crop rotations break up predictable planting cycles, deterring pests from settling down permanently. In fact, cover crops are a habitat for predatory insects, shifting the battle to other issues in crop production, such as weeds. Oh, right. A field of cover crops is a field not overrun by invasive weeds that require time and energy to remove (again and again).

COVER CROPS REDUCE YIELD VARIABILITY DESPITE CHANGES IN EXTREME WEATHER

In 2012, during a severe drought in the Midwest, use of cover crops in rotation prior to planting corn and soybean crops increased yields. On average, corn yields were 9.6 percent higher than those without cover crops. Soybean yields were 11.6 percent higher than non-cover crop counterparts.

Production Return

ARGUMENT 3: COVER CROPS DIVERSIFY INCOME OPTIONS

Cover crops can add income opportunities—like grazing cattle—to the land, which translates to a direct economic benefit. The following is an example using Missouri cash rental rates for grazing land, ideally feeding an animal for one to two months per acre. Costs and yield increases are from farmers participating in the 2016 CTIC cover crop survey while fertilizer and weed management figures are based on USDA ERS data.

*This work was supported by USDA Natural Resources Conservation Services Conservation Innovations Grant award no. 69-3A75-16-003.