The Pine needle scale, Chionaspis pinifoliae (Fitch) is a native insect and a serious pest of ornamental pines in Pennsylvania. It affects pines in landscapes, nurseries and Christmas tree plantations, and is spread by the wind, birds, mammals and the touching branches of trees. Heavy infestations, left untreated, can cause twig and branch dieback.
The most frequently damaged host plants are the mugo pine (Pinus mugo) and Scotch pine (Pinus sylvestris). Other pines affected to a lesser extent are Austrian pine (Pinus nigra), red pine (Pinus resinosa) and eastern white pine (Pinus strobus). It can also infest spruces (Picea), firs (Abies), Douglas-fir (Pseudotsuga menziesii) and cedars (Cedrus).
The adult scales are easily recognized by their white, oyster shell-shaped wax covers, measuring 1/16" to 1/8" long when fully grown. The male have similarly colored markings as the females but are usually smaller. Both male and female have a yellowish spot, the exuvim, on one end. Pine needle scale eggs and newly hatched crawlers are bright red changing to pale yellow then tan, once they start feeding.
There are two generations of pine needle scale per year in Pennsylvania.
The scale uses its piercing-sucking mouthparts to feed on juices from the needles of the host, causing the needles to turn yellowish-brown. Heavy infestations can give the plant a frosted appearance. Untreated infestations may result in sparse foliage and eventual death of the tree.
Katherine Mazzey, Penn State Extension Program Assistant
Michael Masiuk, Extension Agent, Penn State University - Allegheny County
Hoover, G.A. (2002). Pine Needle Scale. Department of Entomology. Penn State College of Agricultural Sciences - Cooperative Extension. http://www.ento.psu.edu/extension/factsheets/pineneedscale.htm
Johnson, W.T. & Lyon, H.H. (1976). Insects That Feed On Trees
Saxe, N. E. (1998). Pine Needle Scale. The Plant & Pest Diagnostic
Shetlar, D. J. (2000). Pine Needle Scale. Ohio State