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United States
Department of Agriculture

Forest Service

Northeastern Area

NA-PR-04-02


Browntail Moth

  Mature caterpillar (Maine Forest Service photo).
  Mature caterpillar (Maine Forest Service photo)

The browntail moth, Euproctis chrysorrhoea, a native of Europe, was first found in North America in Somerville,Massachusetts, in the spring of 1897. The lack of natural control agents contributed to its rapid spread throughout the Northeast. By 1915, the moth’s range included most of the area east of the Connecticut River and as far north as Nova Scotia. During the early 1920’s the range had begun to decline, and by the 1970’s the insect was found on only a few islands in Casco Bay, Maine, and limited locations on Cape Cod in Massachusetts.

Browntail moth caterpillars feed on leaves of many hardwood trees and shrubs. At high population levels,caterpillars may completely defoliate the host. Common host trees and shrubs include apple, oak, cherry,hawthorn, serviceberry, rugosa rose, and bayberry.

Browntail moth caterpillar hairs can cause a skin rash on humans similar to that caused by poison ivy. The rash can be severe and persistent on sensitive individuals. To avoid skin irritation, do not touch the caterpillars.

Overwintering web (Maine Forest Service photo).  
Overwintering web (Maine Forest Service photo)  

Both sexes of the browntail moth have snow white wing sand a tuft of dark brown hair on the tip of the abdomen. Moths are active in late July and August, laying clusters of eggs on the underside of leaves. Caterpillars emerge from the eggs in August and form over wintering webs in close proximity to the egg mass. Limited feeding is do neon upper leaf surfaces in the fall.

In early spring when buds expand, caterpillars begin to feed, often returning to the protection of the webs when temperatures cool. Caterpillars may reach 1.5 inches in length, at which point they are brown with a broken white stripe on each side and conspicuous red spots on the back. Caterpillars mature in late June or early July and pupate in loosely woven cocoons, singly or in clusters, on leaves, trunks, and undersides of branches.The pupal stage ends when the moths begin to emerge approximately 2 weeks later.

Landscape Tip: A good method for controlling browntail moths around the home is to clip the webs during the winter months while the caterpillars are still inside and destroy them by soaking them in water and detergent.


Forest Service Logo. For additional
information,
contact:
USDA Forest Service
Forest Health Protection
P.O. Box 640
Durham, NH 03824
(603) 868-7709
Maine Forest Service
Insect and Disease Laboratory
50 Hospital Street
Augusta, ME 04333
(207) 287-2431
National Park Service
Cape Cod National Seashore 99 Marconi Station Site Road Wellfleet, MA 02667
(508) 349-3785