Studies on the yield analysis of forage crops : I. On the yield promoting factors by the fertilization in the seeding year

Abstract

1. In this paper, a fertilization trial aimed to analyze the developmental factors which determine forage yields of orchard-grass, timothy, ladino clover and red clover, is reported. 2. When the rate of fertilizer was logarithmically increased to the plot field, the numbers of clover per unit area was gradually decreased, while the fresh weight of that was linearly increased. 3. The structure of grass yield was varied each other in the fertilizer experiment and the growth forms were characteristic to each species; in the cases of timothy and red clover, the weight-increase was mainly shared by non-assimilative parts, while in orchard grass, increasing trends of assimilative and non-assimilative parts were parallel to each other according to the rate of fertilizer placement. 4. When fertilizer was multiplied, the increase of yield was due to the increase of width of leaves and leaf-sheaths in orchardgrass, and of tiller numbers, thickness of stems, and width of leaves in timothy, while in ladino clover, it was attributed to the promotion of growth of leaflets and petioles, but of stems in red clover.