Pit-making Oak Scale

From Bugwoodwiki

oak pit scale Photo by James Solomon, USDA Forest Service, Bugwood.org Taxonomy Kingdom: Animalia Phylum: Arthropoda Class: Hexapoda (including Insecta) Order: Hemiptera Family: Asterolecaniidae Genus: Asterolecanium Species: minus Scientific Name Asterolecanium minus Lindinger

USDA Forest Service. 1979. A guide to common insects and diseases of forest trees in the northeastern United States. Northeast. Area State Priv. For., For. Insect and Disease Management., Broomall, PA. p. 123, illus.

This insect attacks most oak species. Light infestation cause trees to lose their vigor, and moderate to heavy infestations may kill branches or entire trees. Trees seem more susceptible to attack during dry weather.

The scale spends the winter as an adult or near-adult on trunks or branches. The damage it causes--a pit-like depression in the bark--is easily recognized. The adult scale is smooth, light yellowish to greenish, and about 1/25 inch wide. The female lays eggs in May and June. Eggs hatch in June and crawlers begin feeding on twigs and branches. As they feed, small pits develop that remain after the scale dies. There is one generation per year.