Abstract
In this report results of the investigation are presented which has been conducted in 1960 on an area of experimental pasture grassland (Ladino clover, Orchard grass and Ryegrass) at our college ground. The purpose of this investigation was to make a study of sampling in the case of yield and coverage survey, especially with reference to size and shape of the sampling unit, and of testing the applicability of the field experimental design to the pasture grassland. A rectangular area, 14x16 meter, was subdivided into 224 plots, each 1 meter square, and coverage of Ladino clover and Orchard grass was weighted in every plot and the variation of various sizes and shapes was tested. Besides, adding the study of size of quadrat to the above to judge condition of the grassland in present and in furture by the distribution type of grass coverage, the following results were obtained. 1) Over 40cm square size of quadrat is fited to determine the distribution of coverage of Ladino clover. 2) The size of quadrat becomes the larger, the experimental error to the coverage and yield of Ladino clover becomes the fewer. But in case of Orchard grass which is recessive, the size of quadrat has the fewer effect on reducing the experimental error to the coverage and yield. 3) The ratio of the sampling area to all experimental one was calculated by the coverage and yield of Ladino clover. The ratio of the coverage and yield was 1.8% and 4% respectively. But this ratio includes 10% experimental error. In order to determine the coverage and yield of pasture grass of the area accurately, a vast numbers of units are required.
