Weeds can reduce the quantity and the stand life of desirable forage plants in pastures and hayfields. These unwanted plants are often more aggressive than existing or desired forage species and compete for light, water, and nutrients. Weeds can also diminish the quality and palatability of the forage available for livestock grazing, and certain weed species are potentially poisonous to grazing animals. Additionally, weeds impact a pasture’s aesthetic value.

Therefore, property owners might want to initiate weed management strategies that reduce weeds’ impact on forage production. However, not all weedy plants are detrimental to pastures or hayfields. In fact, some weedy plants provide nutritional value to grazing animals; thus, owners should make prudent management decisions to determine when or if they should initiate weed control in a pasture or hayfield.

Effect of Weeds on Pasture Yield and Animal Performance

In general, weedy plants are usually not high yielding and are considered to be low in quality. However, livestock often eat many weeds along with the desired forage grasses and legumes. In fact, the dry matter digestibility of several weed species during their early vegetative stage of growth is generally high and comparable to seeded forage species. Crude protein levels are also adequate for consumption by cattle. But, like many cultivated forage grasses, digestibility and crude protein decline as weeds mature. Thus, the greatest benefits in digestibility and crude protein are obtained from weeds and desirable forage species that are grazed during their early growth stages.

On the other hand, some weedy plants are u