抄録
Linear relations of the mean crowding to the mean density were satisfied for both the within-tree and the pooled distributions for pests on apples studied in this paper, i. e., Archips fuscocupreanus WALSINGHAM, Adoxophyes orana FISCHER von ROSLERSTAMM, Lithocolletis ringoniella MATSUMURA, Panonychus ulmi KOCH, Typhlocyba ishidai MATSUMURA and Aphis pomi DEGEER. Using parameters obtained from the regression equations, stop lines of a new method of sequential sampling developed by KUNO (1969) were drawn for both the simple random and the two-stage sampling : the former was for the estimation of the mean density in given tree and the latter in a given orchard. Five stop lines were used actually in the field to test their utilities and it was ascertained that the method presents many possibilities to obtain the necessary information in fieldwark, because it can be applicable well not only to the simple random sampling but also to the two-stage sampling.
