What is in this article?:
A recent survey of farmers by the Conservation Technology Information Center found that cover crops boosted corn yields by 9.6% during the drought year of 2012, and soybean yields by 11.6%. That’s compared to side-by-side fields with no cover crops.
However, cover crops can also lower cash crop yields if not managed correctly, warns Hans Kok, Conservation Cropping Systems Initiative, Indiana. In a dry spring, the cover crop may use up valuable soil moisture that the cash crop needs, says Joe Lauer, University of Wisconsin corn agronomist.
That’s why beginners should start small, Kok says. Instead of planting an entire field of cover crops, he suggests that first-timers put in a few strips at least as wide as the combine. “The combine yield monitor will show you if there is a yield difference.”
Cover crops' roots anchor the soil and nutrients when other crops aren't there to do the job. This is cereal rye.
How do I plant a cover crop?
Cover crops can be seeded with a standard grain drill after corn or soybean harvest, broadcast with a spinner or airflow spreader followed by light tillage, or applied in liquid manure. Cover crops can also be broadcast over the top of maturing corn or soybeans as leaves are beginning to turn, using a high-clearance seeder, airplane or helicopter.
Flying on the cover crop in early September gives it more time to grow, but has drawbacks, in Robinson’s experience. Lower seed-to-soil contact, less precise placement, crop-canopy interference and harvest wheel traffic can all hinder establishment. “I haven’t been as successful with aerial seeding.”