Forage kochia (Kochia prostrata) increases nutritional value, carryingcapacity, and livestock performance on semiarid rangelands
Forage and Grazinglands
Extending grazing into the winter increases the sustainability of livestock production. However, stockpiled range grasses do not meet livestock nutritional requirements. This study compared winter grazing of grass-dominated (untreated) and forage kochia-dominated (Kochia prostrata) (treated) rangelands. Carrying capacity, forage nutritive value, and cattle body condition were determined during late October to early January using landscape-scale trials in Utah. Forage production on the treated rangeland (2,309 lbs/acre) was 6 times greater (P = 0.001) than the untreated rangeland, resulting in carrying capacities of 1.38 and 0.24 AUM/acre for the treated and untreated rangelands, respectively. Grass production was similar (P = 0.564) between the two rangelands, thus forage kochia was primarily responsible for the increased carrying capacity. Forage kochia had higher (P = 0.033) crude protein (11.7%) than the stockpiled grass (3.1%) and met the minimum of 7.0% recommended for gestating cattle. Although both groups of cattle improved in body condition, there was a trend (P = 0.152) for cows in the treated rangeland to improve more in body condition score (+0.7) than the cows in the untreated rangeland (+0.4). This study indicates that forage kochia can improve sustainability of livestock production by increasing rangeland carrying capacity and forage nutritive value.
Waldron, B. L., Greenhalgh, L. K., ZoBell, D. R., Olson, K. C., Davenport, B. W., and Palmer, M. D. 2011. Forage kochia (Kochia prostrata) increases nutritional value, carrying capacity, and livestock performance on semiarid rangelands. Online. Forage andGrazinglands doi:10.1094/FG-2011-0301-01-RS.