How to Manage Pests

Pests in Gardens and Landscapes

Western tussock moth—Orgyia vetusta

Tussock moth caterpillars can be identified by their long hairs and colorful tufts. Young larvae are black with long bristles; older larvae have numerous red and yellow spots, four white tufts of hair, and many more groups of bristles down their backs.

Life cycle


Caterpillars can defoliate deciduous trees in spring. They may also take small bites out of newly set or young fruit; these damaged areas later scab over.


Removing egg masses, newly hatched caterpillars, and cocoons should provide sufficient control in backyard trees. On deciduous trees, an oil spray applied in the winter will kill the egg masses. Spinosad or Bacillus thuringiensis are available for use in most crops.

Western tussock moth caterpillar
Western tussock moth caterpillar

Tussock moth damage to fruit
Tussock moth damage to fruit

Statewide IPM Program, Agriculture and Natural Resources, University of California
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