Cover crop adoption versus the definition of insanity

By Dusty Sonnenberg, CCA

It is said that the definition of insanity is doing the same thing over and over again and expecting different results. “Because we’ve always done it that way,” in some cases, has merit and has allowed farming operations to continue from one generation to the next. At other times, however, repeating the same methods over and over again and expecting a better result has been a death sentence. Sometimes in agriculture, we can fall into the “insanity” trap when considering implementing a new practice. Adopting cover crops typically will fall into one of two camps. Either they are embraced by farmers and fit into the operation, or they are completely rejected because of a bad past experience or because of stories from others who had a bad experience.

In my personal experience as a farmer, cover cropper, and Certified Crop Advisor, I can say with complete confidence that there is no “silver bullet” when it comes to cover crops. While they have a good fit in many operations, they are not right for every farm and in every situation.

Purdue University’s Center for Commercial Agriculture recently published a report titled “Cover Crop Adoption: Results from 5 years of Ag Economy Barometer Surveys”. The report’s results verified what many industry observers have noticed over time. There is both adoption and dis-adoption (or consciously stopping the practice of cover cropping) among farmers for various reasons.

Reasons for cover crop adoption by farmers can vary from participation in programs such as H2Ohio or carbon-type programs that offer incentives to adopt cover crops, to water quality, erosion control, soil health, and weed control benefits realized from their adoption. Other factors may include pressure from landlords to incorporate cover crops on their acres. Each of the reasons has validity in its particular situation.

The use of cover crops to mitigate risk has been argued both as a pro and a con. Some farmers argue that cover crops add risk to an operation because, if not terminated properly in the spring, they can delay planting or act as weeds in the following cash crop. They also add an additional management function in the fall during the hectic harvest season, trying to get them planted in a timely fashion.

The use of cover crops can be considered a positive risk mitigation tool because they have been found to reduce soil erosion, increase soil organic matter, and improve soil structure. All these help improve water quality, water-holding capacity, and soil health. Cover crops have also been found to aid in weed suppression and in mitigating soil compaction.

Research has been conducted on cover crop termination by OSU Extension in their eFields program and also in the Beck’s PFR program.

OSU Extension eFields evaluated the effect of cover crop mixes that winterkill and those that do not, and the impact on soybean yields the following year. In their findings, the soybeans in the non-winterkill cover crop treatment took longer to emerge and were developmentally behind. For the final yield results, there was not a statistically significant difference in the yield of the winter kill cover crop treatment and the control treatment that had no cover crops; however, the non-winterkill cover crop treatment did have a statistically significant yield difference less than the control. It should be noted that the soybeans were planted green into the non-winterkill treatment. Those cover crops were sprayed to be terminated three days after soybean planting. Terminating the cover crop prior to planting the soybeans could have an impact on the final yield results.

In Beck’s PFR study, the timing of termination of cereal rye before soybean planting was explored. The data favored early termination of the cover crops prior to soybean planting compared to termination after planting. It was noted that the Ohio location in the trial showed more favorable results in this practice due to the cooler and wetter clay soils.

Each farmer should honestly evaluate their individual goals for incorporating cover crops on their operations, and it should be looked at farm by farm and field by field. Cover crops have both benefits and drawbacks, which can be impacted differently by the weather from one year to the next. There can be very valid reasons that cover crops do not fit on a farm or in an operation. If cover crops are adopted, farmers need to be aware of the best management practices commonly followed to help enhance success. To simply dismiss cover crops because of someone else’s experience could be a disservice to your operation today and for generations in the future.