Spruce Needleminer

Brown needles and webbing in small clumps that can be easily pulled apart are symptoms of the spruce needleminer. This tiny caterpillar feeds inside the needles, moving from needle to needle and leaving the small exit holes at the base of each needle. The detached needles accumulate in webbing made by the caterpillars. Damage is typically more unsightly than fatal. Control suggestions are to prune off and destroy infested stems if practical. Some resources suggest "washing" the needle debris from small trees with a forceful stream of water from the garden hose. Contact insecticides should be applied when the caterpillars are active, which is early spring (till mid-May according to some resources). Most ornamental insecticides labeled for spruce trees should be effective.

Damage from spruce needleminer

Damage from spruce needleminer

Damage from spruce needleminer

Damage from spruce needleminer

Holes at base of needles from spruce needleminer

Holes at base of needles from spruce needleminer

Adult spruce needleminer moths

Adult spruce needleminer moths

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