There may be a slightly blistered appearance on the leaf s undersurface. Blistering may not be obvious until late summer. Infested leaves typically turn yellow or brown in splotches, are smaller and drop sooner than healthy leaves. A heavy infestation can cause serious loss of leaves and result in death of the boxwood. Insecticides are most effective against this pest when adults have emerged and before they can lay eggs.
Adults typically emerge over a three-week period but live only a few days.
Since mites are so small and early symptoms are not distinctive, it is easy to overlook the problem until a heavy infestation occurs and greater damage has occurred. This pest overwinters as eggs on the underside of leaves. The eggs hatch in the spring. Boxwood mites develop and breed rapidly, resulting in eight or more generations per year. All stages of boxwood mite feed on both leaf surfaces.