Studies on the population of apple leaf miner, Lithocolletis ringoniella Matsumura. II. Estimation of population density within orchard by the sequential sampling based on mean crowding
Yamada, M.; Sekita, N.; Oyama, N., 1971: Studies on the population of apple leaf miner, Lithocolletis ringoniella Matsumura. II. Estimation of population density within orchard by the sequential sampling based on mean crowding. Japanese Journal of Applied Entomology and Zoology 15(4): 248-258
The distribution of Phyllonorycter (Lithocolletis) ringoniella (Mats.), which mines the leaves of apple in Japan, was analyzed by relationship of mean crowding to mean density as proposed by S. Iwao. In all cases, a standing tree was selected at random in each orchard as the primary sampling unit; the secondary sampling unit was a leaf cluster for the first generation and a leaf from the middle part of the shoot for the second, third and fourth generations.