Abstract
Continuous grazing of a mixed sward of Kentucky bluegrass (Poa pratensis L.) and white clover (Trifolium repens L.) as a labor-saving management in the central region of Hokkaido was evaluated in terms of herbage productivity and vagetation characteristics under grazing of Holstein steers (mean initial body weight, 200kg; age, 6 months). The herbage growth rate during 2 weeks after cutting at a 3cm height showed little seasonal variation (4.4 to 5.6g/m^2/day), indicating that the sward is suitable for continuous grazing. The TDN and CP content of herbage increased with the introduction of white clover. The dry weight of Kentucky bluegrass accounted for about 50% of herbage mass, and the rhizome length was about 340m/m^2. Prediction of botanical composition dynamics using the Markovian model indicated that the stability of Kentucky bluegrass is high. Based on the vegetation results and the previously reported animal performance, it is concluded that Kentucky bluegrass and white clover mixture is suitable for labor-saving grazing in Hokkaido.
