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Physokermes piceae

Spruce Bud Scale

Description

Twigs of spruce species may show distinctive “brown galls”. These are, in fact, adult females of the pest. They are round, glossy, as much as 4-6 mm in size. The sweet substance they secrete attracts ants, wasps and bees. The pest is found on tree twigs in groups. The males are much smaller - only 1 mm in size. In May the females lay around 1,000-2,000 eggs. The tiny larvae suck on the youngest shoots. Usually they overwinter at the terminal buds, continue their feeding in spring and then reach maturity. The bark lice most often colonize spruce species aged 10 or higher canopy sections of older spruces. Growth of the shoots is suppressed, the needles discolour brown or die if infested heavily. Usually, however, the insect causes no serious damage.

Symptom

Twigs of spruce species may show distinctive “brown galls”. These are, in fact, adult females of the pest.

Tree Species: Spruce

Part of a plant- attacked: Branch

Pest significance: Harmful

Pest Category: Insects

Invasive Species: No

Present in EU: Yes

Seasonal frequency of occurrence

Seasonal frequency of occurrence