Lambdin, P.L., Grant, J., & Schlarbaum, S. 2008 Rare outbreak of the Oak Eriococcid, Eriococcus quercus (Comstock), on Northern Red Oak, Quercus rubra, in eastern Tennessee.. Proceedings of the XI International Symposium on Scale Insect Studies, Oeiras, Portugal, 24-27 September 2007. ISA Press Lisbon, Portugal 322 pp.

Notes: Abstract: A rare outbreak of the oak eriococcid, Eriococcus quercus (Comstock), was observed threatening northern red oak, Quercus rubra L., within the U.S. Forest Service seedling seed orchard in 1995. In April 1995, ca. 85% of the 787 northern red oak trees in the orchard was infested with the oak eriococcid. By July 1995, the infestation had decreased to ca. 51% of the trees, and by June 1996, it was rarely found. The life history and seasonality of E. quercus were assessed from specimens obtained weekly from branch samples on each of 20 trees representing 10 open-pollinated families. Eriococcus quercus has two overlapping generations, with females undergoing three developmental stages, while males have additional prepupal and pupal stages. Females have a relatively high fecundity rate [x =119 (0-300) eggs/female]. Greater numbers of eggs were observed within the felt-like test of females on tree families 701 and 6662, while fewer eggs were recorded on tree families 323 and 896. The eriococcid settles and feeds on the underside of branches of northern red oak, especially around forks, wounds, and leaf buds. These areas may provide the eriococcid protection from adverse weather conditions and predators. Newly-emerged first-instar nymphs often move to and settle on new tree growth. The eriococcid population was dispersed throughout the tree. Although no parasitoids were discovered in 1995 or 1996, a high population of the lady beetle, Hyperaspis bigeminata (Randall), was observed feeding on gravid eriococcids. Population numbers declined for the overwintering generation from 6.56 individuals/cm in July to 0.14 individuals /cm by November 1995, and specimens were rarely found by June 1996. Both E. quercus and H. bigeminata represent new state records.