Egg -The lemon-yellow egg is flattened on the bottom and slightly flattened on top.
Larva- The larva is green. Except for its small size and six legs, it resembles the adult.
Nymph- The green nymph is similar to the adult except for size.
Host Plants - Boxwoods are the only known host for the boxwood spider mite.
Damage -All stages of mites feed on the upper and lower surfaces of the leaves. As they feed, they apparently inject a toxic saliva, which causes small, yellow, scratchlike spots to form on the upper leaf surfaces. New plant growth seems particularly susceptible to attack. Twospotted spider mites and other spider mites, on the other hand, usually cause tiny chlorotic stipples of discrete dots.
Life History - Overwintering eggs are laid in September and October. In midspring the eggs hatch into six-legged larvae, which crawl about and feed freely for about 3 days. After a resting stage (about 1 day), the larvae molt into eight-legged first nymphs. They feed for about 4 days and then go into a resting stage (about 2 days). After that period, the second nymphs emerge to feed for about 4 days. The final resting stage lasts about 4 days, and then the adults emerge. Mating takes place immediately. Within hours a female may start laying eggs, usually 25 to 30. Because the entire life cycle takes from 18 to 21 days, there are at least eight generations per year.
For specific chemical controls, see the current state extension service recommendations.
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