Abstract
Ten tropical grasses which survived under winter condition in Nishigoshi, Kumamoto were grazed and palatability, volume of intake and density of pastures were investigated. Another experiment for estimation of seasonal productivity was also conducted cutting the same ten grasses at another experimental field. Intake ratio was calculated with the grass weight at the start and at the finish of grazing. In terms of intake ratio and scoring for palatability, sorghum cv "Silk" and carpetgrass showed highest palatability followed by St. Augustinegrass, vaseygrass, switchgrass, little bluestem and knotgrass, while bermudagrass cv "Common", bermudagrass cv "Tifton 44" and weeping lovegrass showed poorest palatability. As the important grasses for grazing in Kyushu, dallisgrass and bahiagrass were scored for palatability in the same grazing field, where dallisgrass showed highest palatability while bahiagrass showed poor palatability. Lower palatability was correlated to higher dry matter percentage of grasses, suggesting lower palatability of heading shoot and poorly growing leaves which have higher dry matter percentage. Plant densities were kept in good condition in both creeping type and erect type grasses under grazing condition except weeping lovegrass which decreased stubble numbers. From the cutting experiment, bermudagrass cv "Common" and bermudagrass cv "Tifton 44" showed even seasonal productivity, and knotgrass, carpetgrass and vaseygrass showed increasing productivity with the advance of season, while St. Augustinegrass, weeping love-grass, switchgrass and little bluestem showed decreasing productivity with the advance of season. On the other hand, seasonal fluctuation of intakes/ha were not same as seasonal cutting yields because of different palatability of each grasses. As a result of total investigation, carpetgrass, sorghum cv "Silk" and vaseygrass were considered to be promising grasses for grazing in Kyushu.
