This experiment was made upon the design of 4^3 (16) [ 3_3] in order to determine the most suitable number of seedlings per unit area (this factor was shown as A), the most suitable length of their roots (as B) and the most suitable planting time (as C) in the transplantation of 1-year old Sugi (Cryptomeria japonica D. Don) seedlings in Sanin District.
The above-mentioned three factors-A, B and C-were respectively divided into four. (Table 2)
This experiment was made on the lands divided into three blocks which had 64 plots respectively.
The size of one plot was 0.5m by 0.5m.
The number of surviving seedlings, their height growth and their weight were examined, and the results are shown on table 4.
The results of this experiment were as follow:
1. The number of transplanted seedlings made little difference to the percentage of the surviving, their height growth and their weight.
2. At the plots where roots were one and half times as long as tops, they showed the highest percentage of the surviving, and the best result in their weight.
And at the plots where roots were one time, the high percentage of the surviving was gained.
3. Time of transplantation proved to be most important among the three factors.
The seedlings transplanted on Nov. 20 produced best results in the percentage of the surviving, their height growth and their weight.
And those transplanted on Apr. 25 were second in the percentage of the surviving, but this results seemed to be happened by the rainfall on day before transplanting and other factors.