Alternative Rotational Grazing Systems at the Beef Teaching Farm

Fifty-six acres of central Iowa corn land were seeded to bromegrass and divided with high-tensile wire into eight seven-acre plots. This bromegrass was fertilized with 70 pounds of nitrogen each spring and fall, 1987-1990. In 1991 – 1995, the nitrogen was increased to 80 pounds both spring and fall. The plots were stocked with 1.3 cow/calf pairs per acre in 1987-1991 and 1993–1995, but in 1992 the plots were stocked with 1.55 cow/calf pairs per acre. The pairs were rotated using two distinct schemes among four cells for about 150 days. The plots averaged 607 pounds of net calf weight per acre per year over nine years. Rainfall was quite variable during the grazing seasons and was reflected in calf performance as well as summer feed costs. This intensive rotational grazing system has greatly reduced both weed population and the need for mechanical clipping.