Carulaspis juniperi
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Pest description and crop damage Scale covering is circular, white, and about 0.06 inch in diameter. Causes foliage to turn brown and twigs to die back.
Management-chemical control
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Chemical Control of Nursery Pests
Apply spray when scale crawlers begin to appear (usually early June) and repeat again 3 to 4 weeks later (early to mid-July).
For more information
Johnson, W.T. and H.H. Lyon (1991), Insects That Feed on Trees and Shrubs, 2nd ed., Cornell University Press (p. 106).