抄録
This investigation has been carried on in the Tsunekichi ADACHI's experimental farm at Shibetsu-cho in Hokkaido, to know the effects of the previous crops, on upland fields to which paddy field were after transfered, upon rice crops. In the first year after transfering the upland field to the paddy field again, the weight of plants, number of available tillers and total weight of panicles indicated marked increase compared with those of the crop on permanent paddy fields. But in the second year no defferences were found, and in a plot (e) the available tillers being rather reduced in its number. As a previous crop of rice plant, the clover was superior to any other crop to increase the yield of rice plants in 6 years rotation of rice-rice-oats(mixed with clover)-clover-clover.
