Seasonal Changes in Frass Ejection by Larval Red-necked Longicorn Beetles, Aromia bungii（Coleoptera: Cerambycidae ）, Infesting Cherry Trees

Abstract

Aromia bungii（Faldermann）（Coleoptera: Cerambycidae） is an exotic pest of Rosaceae trees in Japan. For the purpose of pest control management of A. bungii, this study assessed seasonal changes in its larval frass ejection in the western Tokyo Metropolis. The presence or absence of frass ejection and the number of ejecting holes were evaluated on 294 cherry trees, Cerasus×yedoensis “Somei-yoshino,” in late spring as well as in late summer. Additionally, we assessed the relationship between the basal circumferences of the tree trunks and the presence or absence of A. bungii frass ejection. The proportions of trees with frass ejection doubled from late spring（10%）to late summer （20%）. The occurrence probability of frass ejection was higher as the basal circumferences of the tree trunks were larger. The results of this study will be utilized for pest control management of A. bungii.