Ferguson, A.M. 1989 Asterodiaspis spp., pit scales (Homoptera: Asterolecaniidae).. A Review of biological control of invertebrate pests and weeds in New Zealand 1874 to 1987. CAB International Institute of Biological Control Wallingford Oxon, U.K. 424 pp.
Notes: [Technical communication/CAB International Institute of Biological Control, No. 10]. Asterodiaspis variolosa. the golden oak or pustular scale, and A. quercicola have both been recorded on Quercus spp. in New Zealand. Pest status, background, importations, releases and recoveries are discussed. Pit scales can still be readily found on Christchurch oaks. In winter 1988, the average density of mature scales on 20 current season's twigs from a single tree was 15 (range 1-68). Even at this density, disfigurement of the host is evident.