Utilization and management of mulberry (Morus sp.) for forage: 1. productivity of mulberry-pasture association system

摘要

Dry matter (DM) production, change in botanical composition and viability of mulberry, and growth of mulberry main trunk diameters in mulberry-pasture association subject to harvesting were determined from 1997 to 2000. Mulberries in the associationwere planted at a spacing of 3m between rows and 0.7m between plants (4,762 plants/ha). A mixture of five temperate species was sown among mulberries rows. The association was compared with a sward and mulberry in pure stands. Sward and mulberry were harvested five and three times per year, respectively. Yearly DM production in mulberry-pasture association showed increases of 13 percent and 237 percent in 1997, 32 percent and 192 percent in 1998, 57 percent and 189 percent in 1999, and 34 percent and 380 percent in 2000 over the sward and the mulberry in pure stands, respectively. It was confirmed that the mulberry-pasture association system has very high potential for forage productivity. Moreover the seasonal forage production in the association wasmore even than that in sward due to the contribution of summer-autumn production of mulberry. Weeds and white clover in the sward increased over the duration of the study, while the association maintained the vegetational condition relatively well. Although mulberry maintained a high viability of 97-100 percent over the four years in spite of being harvested three times per year, the vigor of these mulberries seemed to be weakened by the high harvesting frequency.