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Abstract
The twice-stabbed lady beetle
Chilocorus stigma (Say), was studied in two infestations of beech scale,
Cryptococccus fagisuga Lind., to elucidate predator biology and to determine the predator's effect on scale populations.
C. stigma is univoltine in north-central regions of New York and its seasonal occurrence is well synchronized with that of
C. fagisuga. The predator was most abundant in dense scale populations and exhibited a numerical response at hiqh scale densities. The effectiveness of
C. stigma was limited by the propensity of adults to disperse following eclosion, its apparent failure to feed on all-life stages of the scale, mortality during the beetle's pupal stage and high rate of host reproduction. Four species of mites were also noted as predators of
C. fagisuga.
Parent Publication
Citation
Mayer, Mark; Allen, Douglas C. 1983.
Chilocorus stigma (Coleoptera: Coccinellidae) and other predators of beech scale in central New York. In: Proceedings, I.U.F.R.O. Beech Bark Disease Working Party Conference; 1982 September 26-October 8; Hamden, CT. Sponsored by the USDA Forest Service, Northeastern Forest Experiment Station. Gen. Tech. Rep. WO-37. [Washington, DC]: U.S. Department of Agriculture, Forest Service: 89-98.
