The evergreen azalea cultivars are the preferred hosts of azalea lace bugs, although deciduous cultivars may be attacked as well as mountain laurel and rhododendrons. Injury is caused by the adults and nymphs as they feed through piercing, sucking mouthparts. They extract the liquid contents of the leaf tissue through the undersurface. The upper surface of infested leaves become stippled or blanched, and in severe infestations, leaves gradually turn gray to white and eventually may dry up and fall. Cast skins of nymphs are often observed on the undersurfaces.
Damage usually begins on the lower leaves and moves upward.
Since its introduction from Japan in the 1920s, the azalea lace bug has become the most serious pest of azaleas. Females deposit eggs over a 2to 3-month period. The eggs hatch in about 2 weeks and the nymphs develop through five stages. Newly hatched nymphs are colorless but gradually turn black. Depending on temperatures, nymphs take 10 to 21 days to develop into adults.