July 30, 2015
Juniper, arborvitae and chamaecyparis. An infestation of this armored scale causes off-color foli-age, yellowing and dieback of juniper needles. Severely infested junipers may have little to no new growth. Female scales overwinter as adults with eggs; there is one generation per year. Look for crawler emergence beginning early to mid-June, around the time Washington hawthorn or Japanese tree lilac is in bloom.
Several parasitic wasps are among the natural enemies of juniper scale. The overwintering adult female is vulnerable; otherwise the crawler stage should be targeted for treatment with insecticides.
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