Liu, J.X., Liu, K.Y., Yan, S.C., Lin, T., Chi, D.F, Wu, Q.Y., Li, F.R., & Li, C.S. 1997 Regulations of the outbreak of Quadraspidiotus gigas.. Journal of Northeast Forestry University 25: 5-9.

Notes: Experiments were conducted in the Hongqi forest, Daqing city, Heilongjiang province in 1993 and 1994 to investigate the occurrence of outbreaks of Quadraspidiotus gigas (Diaspidiotus gigas) on species of Populus and to determine variables affecting such outbreaks. The density of D. gigas was greater on the middle parts of the tree trunks than on the upper or lower parts. Pest density on the north- and east-facing sides of the trunk was more than double that on the south- and west-facing sides. First-instar larvae emerged in late June and temperatures on the north- and east-facing sides were lower and favoured survival. Climatic data collected in the forest from 1951 to 1977 was analysed and a regression equation proposed to predict future outbreaks.