Nohara, K., Nakao, S., & Nagatomi, A. 2000 A study of the relationship between pesticide treatment and the fauna in citrus groves on Nagashima Island, Kagoshima Prefecture.. Applied Entomology and Zoology. Tokyo 35(2): 271-281.

Notes: This is our third report on the effect of agrochemical treatment to the insect and mite fauna at two native citrus groves of 'Kuroshima-mikan'. The groves are located in Kasedo and Kawatoko on the island of Nagashima, Kagoshima Prefecture. In Kasedo, spraying was practiced in 1974-85 but there was no (or no heavy) spraying from 1986-92. On the other hand in Kawatoko, which was left unsprayed until 1985, only petroleum oil was used once a year (in January) in 1986-87 and in 1990-92. In Kawatoko, Unaspis yanonensis (arrowhead scale) dropped in numbers from 1986 due to the use of petroleum oil. Kawatoko had a rich fauna of insects, especially the effective predators and parasitoids of insect and mite pests. The use of petroleum oil in winter (once a year) was effective against scales and eventually against mites and whiteflies whose natural enemies were uninhibited by the petroleum oil.