, known as pine scale insect or pine needle scale, is an armored scale insect native to North America that feeds on evergreen trees in two families: Taxaceae
. It is common on Scotch and mugo pines, but also can be found on spruces, firs, and Douglas fir. It is a serious and common pest of pine forests and Christmas tree farms, as well as urban ornamental trees. The first instar is small (0.5mm), yellow to orange in color, and motile; at this phase the insect disperses, usually by wind, to other trees. In the second instar phase the scale insect settles on a good feeding spot, digs in using its piercing and sucking mouthparts to begin feeding on plant juices, and becomes sessile for the rest of its life. At this phase the insect also forms an oblong, waxy, white scale covering. When full-grown, the scale covering is about 1-2mm long (females are slightly larger than males), and completely hides the adult's orange-red body. In a heavy infestation that is not treated, white oblong scales can cover the needles of the host tree, making the host tree a frosted or silvery color. Such intensive insect feeding damages cells which in turn causes disruption of photosynthesis, leading to plant discoloration, loss of foliage and plant vitality and eventual death if the infestation is not treated. Outbreaks after mosquito spraying indicate that natural enemies (such as parasitic wasps and predatory beetles) that are susceptible to pesticides have an important role in keeping population numbers in control.