on Monday, January 27, 2020
By Indiana Prairie Farmer
Breeder's Journal: You can't put dollar signs on all these benefits, but they're real!
Read on to find 10 reasons why cover crops help improve crop yields.
You don’t need to spend lots of money or time for cover crops. One of my friends, the late Marshall Alford, Dearborn County, Ind., bought regular wheat from neighbors and asked his fertilizer plant to blend about 80 pounds per acre of wheat with 60 pounds of potash per acre. They spread it after crops were harvested.
He also applied some nitrogen later to help wheat seedlings. You may add some legume and radish seed according to your needs. Be good stewards of the land and help feed the growing world population.
Here are 10 reasons to try cover crops:
1. Reduce disease pressure. My scientific observations comparing cornfields following cover crops with fields of the same hybrids but not following cover crops show cover crops appear to help reduce leaf disease pressures. They appear to prevent pathogens from previous crop residue from infecting new corn. Cover crop residue provides an additional layer of unfavorable host tissue.
2. Slow climate change. Cover crops may help slow climate change by reducing carbon dioxide and increasing the amount of oxygen in the atmosphere through photosynthesis. It’s the same way trees contribute oxygen to the air.
3. Curb soil erosion. We’re losing millions of tons of topsoil every year to erosion. Cover crops not only help reduce erosion but also help improve organic matter content of the soil and improve yields.
4. Prevent nutrient leaching. Cover crops prevent nitrogen, phosphate, potash and other nutrients from leaching, and keep them in the upper layers of the soil where they can be easily available to the following crop. It’s even more important to capture unused nitrogen after drought.
5. Improve carbon-to-nitrogen ratio. Cover crops improve root mass and help in developing a healthy carbon-to-nitrogen ratio. Root mass becomes so important in drought conditions for capturing water.
6. Minimize weed pressure. Weed pressure is reduced following cover crops. Even early weeds can hurt crops. Reduction in weed pressure will improve crop yields.
7. Break up soil compaction. Cover crops can sometimes help break down hardpans and compacted layers. For example, radishes that can grow roots almost an inch thick and more than a foot long can penetrate compacted layers.
8. Find more earthworms. One big benefit of cover crops is the increase in earthworms. Some estimates indicate that populations of these useful worms may increase by 15 to 32 times following cover crops.
9. Increase water retention. Cover crops help increase organic matter content and improve cation exchange capacity of the soil. High organic matter helps improve water retention and increase yields.
10. Decrease fertilizer needs. The amount of fertilizer needed may be reduced over time with the use of cover crops. The only caveat is that if you plant corn following a cereal rye cover crop, you need some nitrogen as starter. You don’t need more overall nitrogen — you just need to adjust timing.
Nanda is director of genetics for Seed Genetics Direct, Jeffersonville, Ohio. Email him at firstname.lastname@example.org or call 317-910-9876.