Juniper Scale
Contact: Eric Day, Manager, Insect Identification Laboratory
August 1996
Juniper Scale
Homoptera: Diaspididae,Carulaspis juniperi (Bouche')
Plants Attacked
Juniper sp.
Description of Damage
Needles in area of feeding become
yellowish or straw colored and die. Damaging stages - all
stages.
Identification
Males most easily observed. They have an
elongate white covering with a yellow cap at one end. The female
coverings are circular and tan in color. The female under the
cover is also circular and yellow in color.
Life History
Fifteen to forty eggs are laid beneath female
scale about the first of May. Hatching occurs about the first of
June. The crawlers settle shortly after hatching and begin
feeding. The females have 3 instars, the males, 5 instars. The
males do not overwinter. They develop by fall, emerge, mater,
and die soon after. One or two generations per year.
Overwintering stage - fertilized adults.
Control
At least 2 sprays 1 week apart beginning about the
first of June. Eggs hatch over a period of 2 weeks or more.
Dormant sprays help but are not thoroughly effective. Oils are
not as effective as lime sulfur, but lime sulfur severely stains
white paint, woodwork, and stone work.
Remarks
We still lack a thoroughly effective control. Control
measures should be applied for 2-3 years to clear up
infestations.
