Legumes contribute to forage yield and quality

Livestock producers know that the best way to increase forage production and quality, and reduce the cost of grazing or feed, is to include a legume in their forage mix when seeding pasture or hay. Legumes such as alfalfa and cicer milkvetch are productive and have higher protein and energy levels than grasses at similar times throughout the growing season. The question is often how much of a yield and quality benefit do legumes provide.

Two relatively recent demonstrations funded through the Agriculture Demonstration of Practices and Technology program (ADOPT) at the Melfort Research

Farm, provided examples of this benefit for the parkland area of the province. In these demonstrations, four years of production was compared between unfertilized grass and alfalfa grass mixtures in one demonstration seeded in 2008 and unfertilized cicer milkvetch and cicer grass mixtures in the other seeded in 2013.

Alfalfa is well known for contributing to increased yield and quality in both pasture and hay. It is the most productive legume producers have for hay and pasture throughout the province. The effect of cicer milkvetch on yield and quality is less well known. Cicer milkvetch is a non-bloat legume that is suited to grazing in moist areas of the province. It is hardy, long-lived and productive where it is adapted.

Cicer will generally not yield as well as alfalfa but, unlike alfalfa, it can increase in forage stands as they age, in some cases competing quite well with the grass crop it was seeded with.

One of the concerns often heard about cicer milkvetch is it is relatively slow to establish if seeded with a companion crop. When seeded without a companion crop in a mixture with perennial grasses, cicer milkvetch generally establishes better. At Melfort, cicer established well and produced a productive stand the year after seeding. Currently, another concern with cicer milkvetch is the lack of commercial rhizobium inoculant that is needed for this legume. Without this inoculant the amount of nitrogen fixation within the plant is reduced.

The yield results of these two projects indicated, that both the alfalfa and cicer milkvetch grass mixtures yielded higher than when the same grass species were seeded without each legume. For example, an unfertilized cicer milkvetch hybrid brome mixture out-yielded hybrid brome seeded alone by about double in the fourth year of production. In the alfalfa demonstration, alfalfa grass mixture yields were twice those of the grass only treatments by the third year of production. Protein and total digestible nutrient (TDN) levels were increased in grass-legume mixtures compared to the grasses seeded alone.

For more information on this or other forage topics, contact your local Saskatchewan Agriculture Regional Office.