Rhododendron varieties that have thick, leathery leaves often escape infestation. They are oval shaped, reddish colored, with eight legs. The immatures appear the same, only a little smaller and with six legs. The red eggs overwinter on the undersides of leaves. There are several generations per year.
Most activity takes place during the cooler weather of spring and fall.
During the heat of summer, the life cycle is in the egg stage. Leaf damage is visible as white stippling damage on both sides of the leaf. In a heavy infestation, the leaves will turn brown, die and may drop off the plant. The undersides of the leaves are often coated with hatched egg shells and shed skins from molted mites. Monitoring Look for stippling and mites on the lower leaf surface from April through June and again from September through November.