Source: Michigan State University Extension

By Frank Wardynski

Cover crops have increased use over recent years to assist crop farmers to capture soil nutrients, protect soil, preserve moisture and generally improve soil health. Many cover crops are grown during fallow time between the main cash crops grown on the farm. Livestock producers can reap these same conservation benefits while capturing forage nutrients by grazing or harvesting as hay/silage.

Some cover crops are grown to specifically aid in production of the next crop. Legumes are frequently grown because of their ability to fix nitrogen (N). Much of this N can be utilized by the next or subsequent crops grown in future years. Grazing legume cover crops provides livestock with high quality feed while returning some of the N back into the soil via manure and urine.

Other cover crops may be planted with intentions of improving soil structure in no-till systems. Especially on clay soils, crops such as oilseed radish, turnips, soybeans and field peas have the ability to break compaction and prepare soil for a more favorable seed bed in no-till systems. These cover crops are particularly useful on clay soils. Michigan State University Extension educators frequently recommend utilizing no-till systems on heavy clay soils to establish grazing crops. Tilled clay soils are easily damaged from intense hoof traffic if soil moisture conditions are too wet.

Grazing of cover crops appears to provide greater soil improvement benefits than harvesting forages as a stored feed. Harvesting forages as hay or silage removes organic matter that could potentially remain of the field and be incorporated back into the soil. The point isn’t to indicate that harvesting forages is detrimental, but rather simply that grazing the forages can provide enhanced soil improvement benefits. 

For example, winter rye is frequently planted in the fall as a cover crop after a grain or silage harvest. Harvesting this whole plant the following spring as hay or silage allows high quality feed resources to be captured and is more beneficial to soil health than leaving the field lay fallow through the winter months.

Grazing or harvesting cover crops offers livestock producers the opportunity to capture highly digestible nutrients for their animals and provides benefits to the soil in their cropping systems. For more information about utilizing cover crops as a livestock feed source contact me the ruminant MSU Extension educator at wardynsk@anr.msu.edu or 906-884-4386.