Optimal stocking rate for cow-calf enterprises on native range and complementary improved pastures

Abstract

Complementary pasture-native range systems are known to increase production per cow and per hectare of cow-calf enterprises, but the proper ratio of complementary pasture to range and the optimum stocking rate on each has not been established. From 1978-1985, crested wheatgrass [Agropyron desertorum (Fisch.) Schult.]-native range and meadow bromegrass (Bromus biebersteinii Roem. and Schult.)-alfalfa (Medicago sativa L.)-native range systems were grazed by cow-calf pairs and yearling heifers at a range of grazing pressures. Gains of all classes of cattle and conception rate of cows remained constant across a range of low grazing pressures, then declined linearly as grazing pressure increased. These response functions were used to calculate economically optimum pasture-to-range ratios and stocking rates at 1980-1984 average costs and prices. The optimum ratio of crested wheatgrass to range at estimated yields, costs and prices was 1:3.94 (0.66 ha of wheatgrass and 2.60 ha of range per animal unit), which returned $35.70/ha to land, labor, and management. Usual ratios of 1:8 to 1:12 were much less profitable. At optimum stocking rates, the brome-alfalfa-native range system returned only $3.38 more per hectare than the crested wheatgrass-native range system, not enough to pay additional cost of irrigation. Optimum ratios, stocking rates, and returns will vary with levels of forage production, production costs, and livestock prices.