2023 Volume 69 Issue 3 Pages 120-128
To clarify the changes in botanical composition and herbage production, and factors affecting them under labor-saving management, Holstein raising cattle were put out to pasture on Kentucky bluegrass (Poa pratensis L., KB) and white clover (Trifolium repens L., WC). mixed sward in Hokkaido for 16 years. To reduce surplus herbage, stocking was initiated at 5 cm plant length, and the entire amounts were fertilized in late June after spring flash. The annual mean value of the dry matter weight ratio of Agrostis alba L. coincided with the change in soil potassium content. By keeping the fertilizer component content in the soil within the standard range, the annual means of dry matter weight ratios of KB and WC were maintained in the ranges of 39-65% and 9-39%, respectively. The annual mean of daily dry matter production fluctuated in the range of 2.1-5.3 g DM/m2 and increased with increasing total precipitation in May-October and the annual average dry matter ratio of WC. Based on our reports’ results, it was considered that KB-WC mixed sward in Hokkaido has a certain degree of herbage production under continuous stocking conditions under stable botanical composition for a long period.
