Farmers harness benefits from cover crops
A growing number of farmers in Maine have discovered the cover — and for some very good reasons.
By cover, I’m talking about cover crops — plants established when cash crops are not being grown. Cover crops are planted because of their excellent benefits, including improving the health and function of soil. This leads to better nutrient cycling, improved water infiltration, and more consistent yields over time. Cover crops also suppress weeds, prevent erosion, control diseases and pests, as well as help pollinators. And, cover crops can help reduce compaction without the need for deep tillage. Planting cover crops is one of several key steps that farmers can take to improve soil health along with rotating crops, including cover crops, and using no-till cropping systems.
Farmers not familiar with how mixtures of cover crops work together might ask, “Why would I want to plant a cover crop that uses up all my water?”
One answer is that using diverse annual cropping rotations and cover crop combinations, increases soil organic matter. For each 1 percent increase in organic matter, there is a 25 percent increase in water holding capacity and up to 30 pounds an acre more available nitrogen. While cover crops use some water in the soil profile to grow, they simultaneously improve the soil structure by building soil aggregates, recharging the water in the soil profile though increased infiltration, and providing armor for the soil surface, thus preventing erosion and the concomitant pollution as soil that is planted rarely erodes.
When a variety of cover crops are planted — especially when 10 to 12 plant species are planted together — they increase biological activity in the soil and speed soil health improvements. When only one cover crop species is planted, the single crop or monoculture will struggle in a drought or when facing pests. But the more diversity you have, the more plant balance you have above ground and the better the soil biology balance below ground. Many farmers are working with USDA’s Natural Resources Conservation Service to choose the right mix or cocktail of cover crop seeds for their farm.
Visit me.nrcs.usda.gov or the local NRCS field office for help on choosing the right conservation efforts for your land: Autumn Birt, District Conservationist, Belfast office, 338-1964 ext. firstname.lastname@example.org. And be sure to visit online for other educational resources: Knox-Lincoln, knox-lincoln.org; and Waldo County, waldosoilandwater.org.
Submitted by Hildy Ellis, Knox-Lincoln Soil & Water Conservation District Coordinator, with assistance from USDA Natural Resources Conservation Service.