Abstract
We have taken up four grasses and legumes (or-chard grass, Kentucky 31 fescue, tall oatgrass, alfalfa, red clover, birdsfoot trefoil and Ladino clover) with a view to examine their adaptability to Sanyo district. For three years (1960-1962), we have investigated the effect of cutting upon yield and its seasonal distribution of pasture plants in pure stand and the following results were obtained: (1) The comparison of 3 years' total yield among them disclosed that Kentucky 31 fescue and Ladino clover yielded highest through any stage of growth at the time of cutting. (2) Increase in the number of cutting (for example, cutting when they were 30 cm in height) caused decrease in yield. This was especially so in perennial ryegrass. As for legumes, its tendency varied with species. Namely, alfalfa and red clover decreased and there was almost no change in Ladino clover. (3) Each of the pasture plants showed a seasonal distribution of yield peculiar to them. The difference in growth stage at the time of cutting scarcely evident in this tendency. Kentucky 31 fescue had the smallest seasonal variation. Orchard grass continued excellent growth from April to the beginning of July and lost growth vigor in summer. This summer depression of growth grew worse with a lapse of year. Tall oatgrass was vigorous in May and June, and it declined slightly in summer season, recovering its growing in fall. Perennial ryegrass grew very vigorously in April and May, but with the rise in temperature it declined, resulting in marked summer depression of growth. The recovery of growth in the fall season could not be expected much. Alfalfa made a small varition of yield distribution. Birdsfoot trefoil showed vigorous growth in the spring season of the first year next to red clover, but with a lapse of year it declined in growth conspicously. As to the variation of distribution, it was smaller next to alfalfa. The growth of Ladino clover in spring season was vigorous but its growth in summer and fall season declined after the second year. Red clover grew very vigorousely from April to July and declined after summer season. It showed a conciderable recovery in the next spring, but its yield decreased year after year. (4) Concering the change of yield with a lapse of year, authors findings were follows: The richest yield of grasses was obtained in the second year it decreased, but recovered in the third year. Among legumes, alfalfa had the highest yield in the second year but other legumes decreased with a lapse of year. Those which showed smaller yield variation among pasture plants were Kentucky 31 fescue and alfal-f a, and those with larger variation were perennialr yegrass and red clover.
