Coates Tree Service, Inc.
BUG OF THE MONTH
Piñon Needle Scale (Matsucoccus acalyptus)
Piñon needle scales are small black dots or bumps on the surface of one-year old piñon needles. These tiny, sap-sucking insects kill the needles and seriously weaken the tree. Reduced new growth and stunted needles are common on trees suffering repeated attacks. Heavily infested trees are more susceptible to attacks by other insects and diseases.
Adult, wingless females emerge from scale coverings in late winter or early spring and mate with winged males. Mated females lay yellow eggs in clusters held together by white, cottony webbing around the root collar, on undersides of large branches, in branch crotches, or in cracks of rough bark.
Nymphs, called crawlers, emerge about five weeks later. They climb to the ends of branches and settle on the previous year’s new growth. After inserting tube like mouthparts into the needle they become immobile, cover the body with wax, and turn black.