Dairy and other livestock farmers are blessed with manure to be able to meet many crop nutrient requirements. Manure is a great source of nutrients for crop growth and it also adds organic matter to the soil. One limitation of livestock manure is that it is difficult to apply enough to meet all nutrient requirements without over supplying phosphorus. Most producers are left with having to cut back on the manure applied to stay within the phosphorus guidelines and then purchase commercial nitrogen and potassium to balance it all out. With nitrogen fertilizer costs going up, producers are looking for other alternatives.
Welcome back to an old friend with a new twist, cover crops. It used to be that we looked at cover crops as a way to “cover” the soil when we didn’t have a crop actively growing. Usually that meant that cover crops were used after harvest to cover the ground through the winter, or when we had a piece of ground that we wanted to keep fallow throughout the summer. While those uses are still very important, cover crops are being used in a much broader way now and the cover crops themselves have become much more diverse.
At a recent field day in Charlevoix County we looked at some of the broader uses of cover crops. The program, hosted by Doug Warner owner of H & D Farms, included presentations by Mark Matthews of Indiana/Ohio Agri Service and Christina Curell of Michigan State University Extension. Doug has used a triticale/pea mixture for a number of years as a cover/nurse crop for his spring alfalfa plantings. As a nurse crop this cover crop mixture has helped Doug control weeds in his new alfalfa stands, allowed for a lower seeding rate of alfalfa (10 pounds per acre) and has given him a large volume of decent quality forage in his first cutting (over 4 tons DM in some years). At the field day, Warner and other participating producers looked at ways that they could expand the use of cover crops, including seeding into existing corn fields.
In the weeks to come, Warner and other area producers will be seeding a mixture of annual ryegrass and crimson clover into standing corn fields. The mixture will be spread at the rate of 10-15 pounds per acre and will be broadcast over the corn when the corn is about 24-30 inches tall. The goals are to deliver nitrogen to the soil (clover), hold nutrients in place and provide a cover throughout the winter. The mix being used is just one offered by Matthews and being studied in numerous research plots by Curell.