Interspecific competition between two parasitoids of the mealybug, Oracella acuta (Lobdell) (Hemiptera: Pseudococcidae)
The pine-feeding mealybug, Oracella acuta (Lobdell), was accidentally introduced and established in Guangdong Province, China, in 1988 (Sun et al. 1996, J. For. 94: 27-32). It spread rapidly through the extensive plantations of exotic slash pine, Pinus elliottii Englem. var. elliottii, a species native to the U.S. Total volume growth loss has exceeded 33% in some cases, though tree mortality has not been reported (Ren et al.2000, Natur. Enemies of Insects 22: 140-143). Oracella acuta is seldom a pest in the U.S. due to an effective natural enemy complex (Clarke et al. 1990, Environ. Entomol. 19: 99-103; Sun et al. 2002, J. Entomoi. Sci. 37: 177-181). Outbreaks occur when natural enemy populations are drastically reduced, particularly by insecticide applications (Clarke et al. 1992, J. Econ. Entomoi. 85: 1246-1252).