Close to 4,056,000 rhododendrons are grown or collected by Southern nurserymen each year. Although sometimes difficult to maintain in the Piedmont and Coastal Plain, rhododendrons are highly desirable landscape plants because of their attractive flowers, variable growth habits, and leaf texture and color. Rhododendrons are not highly susceptible to insect pests, but they are occasionally beset by rhododendron borers, rhododendron lace bugs, and two kinds of weevils.

KEY TO COMMON AND IMPORTANT RHODODENDRON PESTS

1. Rhododendron borer -Heavily infested branches weak, breaking easily; leaves wilt and turn brown; holes in infested branches with fine sawdust; white caterpillars in tunnels.

2. Rhododendron lace bug -Chlorotic spots on upper leaf surface, numerous dark spots of insect excrement on lower leaf surface; small, dark, spiny insects and slightly larger (3-mm), lacy insects on lower leaf surface.

3. Rhododendron tip midge -New growth distorted, leaf margin curled under tightly; small (1.3-mm) maggots inside cavity formed by curled margin.

4. Weevils -Leaves notched on margin, sometimes wilting during hot weather; eventually heavily infested plants may die.

   1. Black vine weevil -Damage to leaves done late at night; white grubs feeding on roots during growing season; adult weevil is black .

   2. Japanese weevil -Damage to leaves occurs during daylight; larvae are white grubs, which probably feed on the roots during the growing season

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