Overwintering females can be found near the base of terminal buds on spruce shoots and the undersides of needles of Douglas-fir. Apply a dormant oil spray to crevices of bark on terminal twigs and bases of buds on susceptible hosts. Do not apply oil to Blue spruce since it may cause discoloration of the foliage. Use instead an insecticidal soap or a registered insecticide. Treat the spruce in mid to late April; the Douglas fir in early May.