{"id":4022,"date":"2013-01-29T14:32:31","date_gmt":"2013-01-29T19:32:31","guid":{"rendered":"https:\/\/extension.umaine.edu\/home-and-garden-ipm\/?page_id=4022"},"modified":"2025-07-01T14:05:51","modified_gmt":"2025-07-01T18:05:51","slug":"lymantria-dispar","status":"publish","type":"page","link":"https:\/\/extension.umaine.edu\/home-and-garden-ipm\/fact-sheets\/common-name-listing\/lymantria-dispar\/","title":{"rendered":"Spongy Moth (new name for an old pest)"},"content":{"rendered":"

\"mature<\/a>Spongy Moth<\/strong> (Lymantria dispar)<\/em>, introduced accidentally in 1868\/1869 into Massachusetts from Europe, is a major pest of hardwood trees in the eastern U.S. and in bordering areas of eastern Canada. Spongy moth caterpillars feed on most hardwood trees, except ash. They prefer oak, poplar, gray birch and fruit trees.\u00a0 When half grown or larger, the larvae are also likely to feed on evergreens, including Colorado blue spruce, Picea pungens<\/em>.\u00a0 As the number of spongy moth larvae in an area increases, their favorite food sources become depleted.\u00a0 The larvae are then likely to feed on other ornamental trees and shrubs.<\/p>\n

Late-stage caterpillars are hairy, dark and easily distinguished by five pairs of blue spots on the front body segments and six pairs of red spots on the back body segments.\u00a0 Fully grown larvae are 1-1\/2 to 2-1\/2 inches long.\u00a0 About 70 percent of their food is consumed during this stage of development; they are able to strip a tree overnight.\u00a0 Female spongy moths cannot fly.\u00a0 Consequently, after mating, they do not move far from their pupation site to lay their single mass of 500 or more eggs.<\/p>\n\n\t\t