Caterpillar surge defoliating trees in Middle Peninsula

The Virginia Department of Forestry has received  calls from homeowners concerned about sudden defoliation on their local hardwood trees. Staff have surveyed the area and confirmed at least three outbreaks of the variable oak leaf caterpillar.

Common throughout eastern North America, this native caterpillar is an expected late summer defoliator in Virginia but is usually present in lower numbers. Occasionally, as has happened this year, variable oak leaf caterpillars will “outbreak,” characterized by a population spike in a local area. This can result in severe defoliation across a community, town or county.

The last known outbreak in the Middle Peninsula was recorded in 2017.

The caterpillars prefer white oak species, but will attack a variety of hardwoods. Young larvae skeletonize, or strip, the leaf, leaving behind the veins. Older larvae devour the entire leaf except the stalk and primary veins.

Fortunately, insect parasites and predators typically cause caterpillar populations to fall after one or two years of heavy activity. Several natural predators have already been observed eating variable oak leaf caterpillars, including a metallic green calosoma beetle known as the “Caterpillar Hunter.”

Chemical control may be used to protect high value trees, but should be applied to landscape trees when caterpillars first emerge.

Visit the DOF website for information on variable oak leaf caterpillars and other late summer defoliators.