Q: What are these caterpillars I am finding on my azaleas? I picked off 47 yesterday.
A: Wow, 47 caterpillars from one bush; that is amazing. The caterpillar you brought into the office is the azalea caterpillar, Datana major. It is found in Florida from July through October on azaleas (Rhododendron spp.). Often, the caterpillars completely defoliate much of the plant before they are detected. While the caterpillar appears to be a stinging variety; it is harmless to humans and can be picked off the bushes by hand, which you discovered when you were removing them from your plant. The caterpillars seem to prefer indica azaleas, but they have been found on blueberries, red oak and even apple trees. The semi-skeletonized leaves dry up, turn brown, and remain on the plant for several days. If disturbed some of the caterpillars drop one or two inches below the infested leaf and hang by a silken thread. When it is disturbed, the caterpillar raises its front and rear ends into the air. Young larvae skeletonize the leaves and the larger ones eat the entire leaf. In some parts of the South there may be a partial second generation, but one generation per year is usually the rule. Most of the damage in the southeast United States occurs in August and September, but in Florida it continues through October.