Juniper Scale (Carulaspic juniperi)
Mature female covers are circular, white, and about 1/16 inch in diameter. Male covers are smaller, elongate, oval, and white. Shed skins incorporated into the cover are yellow. There is one generation a year. Adult females overwinter on needles.
This imported armored scale insect prefers juniper, but has also been collected from Leyland cypress and cedar. Yellow crawlers are present in late spring.
Dormant oil spray will reduce the number of adults that successfully overwinter, but usually does not provide adequate control. Use horticultural oil or insecticidal soap to control crawlers in late spring. Systemic insecticides may be used to reduce heavy populations of scales in late summer and fall.