Stems and leaves are covered with white, cottony, cushionlike masses; brown, crusty bumps; or clusters of somewhat flattened reddish, gray, or brown scaly bumps. These masses don''t move when touched. The bumps can be scraped off or picked off easily. Leaves turn yellow and may drop. A shiny or sticky material may cover the leaves and stems. Sooty mold may develop on the sticky substance.
Spray with an insecticide labeled for this pest, following label instructions. In spring, before new growth begins, spray the trunk and branches with a horticultural oil.