Survey Finds Cover Crops Boost Corn, Soybean Yields

Results of a national cover crop survey confirmed that growers who use cover crops see a yield advantage compared to those who don’t. 

The NRCS, Sustainable Agriculture Research & Education (SARE) and Conservation Technology Information Center recently released the findings from their second annual cover crop survey, which was conducted in the winter of 2013-14. Almost 2,000 growers, which consisted of cover crop users and non-users, responded to the survey, which focused on the benefits and challenges of adopting cover crops.

Here are a few highlights the survey found in regards to yield advantages for cover crop users:

• The national corn yield average for cover crop users was 3.2% higher than non-users, with an average yield advantage of 4.98 bushels per acre. Soybean growers using cover crops also saw an average yield boost of 2 bushels per acre, or 4.3%, over non-users.
• These national yield increases are lower than the first survey from 2012, which found that cover-crop users gained an extra 11.1 bushels per acre in corn and 4.9 bushels per acre in soybeans. The report notes that cover crops’ moisture-saving benefits during the 2012 drought may explain why growers experienced a greater benefit that year.
• The report compared the average corn yields of 16 states. It found that of those states, Missouri and Iowa were the only two that did not see higher corn yield averages with cover crops. It also found that Nebraska had the biggest difference in corn yield between cover-crop users and non-users, with cover-crop users averaging 153.7 bushels per acre, more than 13 bushels above non-users’ yield average of 139.9. 
• The report also looked at the yield differences in soybeans between 15 states, and found that Kentucky and North Carolina had the biggest discrepancy in yield between cover-crop users and non-users, with cover-crop users seeing a 6.5-bushel increase for both states. All 15 states had higher soybean yields with cover crops.
• The survey results also indicate that the longer you use cover crops, the greater yield benefit you’re likely to see. In the 2013-14 survey, corn growers with 0-3 years of cover crop experience saw an increase around 2 bushels per acre, while those with more than 4 years experience saw a boost of almost 7 bushels per acre. A higher yield increase also held true for soybean growers. Those with 3 years experience or less had a 1.09-bushel-per-acre advantage, while those with 4-plus years gained 2.84 bushels per acre.