The role and importance of cover crops on livestock production and sustainability of agriculture

Cover crops are annual plants that can be used to improve soil quality and health during the non-harvesting season of cash crops.  Cover crops promote soil coverage, suppress weeds, recycle soil nutrients, and reduce erosion, pests and diseases, while increasing soil organic matter.  They also reduce nutrient runoff and leaching. Cover crops encompass grasses, legumes and brassicas. Legumes use a process called nitrogen fixation, which takes the nitrogen out of the atmosphere to turn it into nitrogen available for plants in the soil which can be used for a plant’s benefit. Examples of legumes include pea, soybean, and red clover. Grasses and brassicas are planted to improve water infiltration and soil physical characteristics, besides adding organic matter. They are also used to keep as food by soil microbes. Some examples include oats, rye, and mustard. In livestock production systems, the optimal way to incorporate cover crops is to use mixtures to improve the overall forage production and soil quality.

Figure 1. Livestock grazing cover crops mixture in Blackville, SC.

Cover crops can be very beneficial when used as forage crops, not only for their soil benefits, but also for their significant production and economical savings they allow producers to make.  When using cover crops for forages in grazing systems, many factors must be considered. Cover crops chosen are based on the season, time of year, climate, soil type, location, and cost of seeds. Several cover crops can be used for forage production, including oats, small grains, peas, ryegrass, vetch, sorghum sudangrass, brassicas, and clovers. The suggested winter cover crops within South Carolina include winter peas, turnips, annual ryegrass, small grains, oat, clovers, radish, and rye. The most common livestock to graze on cover crops are beef cattle. Rather than feeding cattle with off-farm sources, cover crops can reduce feed costs.  The savings come from lower requirement for equipment use for forage harvest costs (diesel, labor costs), storage and transportation. While, there will be a return of nutrients to the soil because when cattle graze the land with the cover crops, their urine, and manure are recycled and improve soil biology, fertility and health.

Besides cattle, small ruminants and horse systems also benefit of using cover crops to extend the grazing season. When selecting adequate cover crops for sheep, you must be careful to avoid species that may cause health issues. Legumes provide a great source of protein to livestock so it is a good option to include in their diet. In general, in horse operations, the most used cover crops are clovers,  rye, and annual ryegrass. Farmers find that using cover crops for horses extend their grazing season, but, similarly to sheep, there are some species that can cause health issues in horses. For example, high carbohydrate concentration in the diet can lead to laminitis in horses and donkeys, so most horse operations avoid including oats in the pasture mixtures.

Cover crops are a great source of food for livestock production and allow farmers to save money since they extend the grazing season while improving animal performance and soil quality. Through grazing, livestock support plant decomposition and nutrient recycling. Legumes provide a great source of protein for livestock and support improved animal performance, while adding nitrogen into the soil. When picking out cover crops for livestock species, you have to be careful to avoid species that may be impact their health or could potentially be toxic or poisonous to animals.

Written by

Lily James, High School Sophomore*

Liliane Silva, Forages Specialist

*Lily James is a sophomore high school student who interned under Dr. Silva during summer 2024. Lily plans to ecome a veterinarian and get her degree from Clemson University.