Description, biology and damage Mature scale are almost circular, 0.06 inch in diameter, and yellowish brown to black. Young hatch in spring and summer. Scale feeding is restricted to the needles and results in their becoming splotched with yellow patches. Heavy infestations cause premature needle drop and may result in death of the tree. Affected trees often display a thin crown, yellow or reddish coloration, and a shortening of the needles. This insect attacks various species of pine, ponderosa most commonly, as well as Douglas-fir and hemlock. This scale overwinters as immatures. The crawlers start to disperse to fresh foliage in spring. There may be one to three generations per year.
For biology, life history, monitoring and management
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