September 28, 2007

Some pastures have a lot of weeds this fall and it may be tempting to graze them hard enough to provide control. This may not be the best solution for overall pasture health.

While many weeds can provide satisfactory protein and energy for cattle when eaten, controlling weeds with heavy grazing pressure might not be healthy for the pasture.Every pasture has millions of weed seeds in the soil and the potential to become weedy. Since some pastures stay relatively clean while other pastures become weedy, other factors undoubtedly influence the weed population. Simply grazing or controlling weeds by spraying or cutting does little to prevent weeds from coming back again unless these other factors are changed to better support desirable plants.

To control weeds, it is much more important to manage grazing to support healthy desirable plants than to weaken or remove unwanted weeds. Grazing that allows sufficient leaf area to remain following grazing to support rapid regrowth, allow good winterizing, and hold snow and rain moisture on the land rather than running off will benefit the desirable grasses and legumes. Giving pasture plants adequate time to recover from grazing before grazing again is another way to improve or maintain pasture health and strengthen the competitive ability of desirable plants.

Weeds in a pasture indicate that the pasture itself and the desired plants in it are not in a healthy condition. For improvement to occur, controlling weeds is not enough. Changing management to strengthen desired grasses and legumes also is essential.

Bruce Anderson
Extension Forage Specialist