Every fall, Macomb County MSU Extension does a Spongy Moth survey for egg masses. Homeowners who believe they have Spongy Moth egg masses on their property should contact the Macomb County MSU Extension office at 586-469-6432 and request to be included in the fall survey. Calls MUST be received by November 30 to be included in this year’s survey.
Spongy Moths (Lymantria dispar), formerly known as Gypsy Moths populations can grow very large, and they can become a nuisance and detrimental to a homeowner. Large populations can defoliate trees. Trees with other stress factors, such as drought, could be damaged by this type of defoliation. Several years of recurring defoliation will eventually kill trees. The large number of caterpillars and their waste (frass) can prevent homeowners from using their outdoor spaces in the summertime. In some cases, the caterpillars can cause allergic reactions in people.
The female moth lays the egg masses in July. Egg masses are a buff yellow-brown color, typically tear-drop shaped and up to 2 inches in length. Masses are laid in protected areas on trees as well as on places such as play equipment, lawn furniture, and soffits on homes, garages, vehicles and wooden fences. Egg masses laid in mid-July through August will survive the winter and hatch in the spring producing hundreds of caterpillars from each egg mass.
For more information, contact MSU Extension at 586-469-6432.
MSU is an affirmative-action, equal-opportunity employer. Michigan State University Extension programs and materials are open to all without regard to race, color, national origin, gender identity, religion, age, height, weight, disability, political beliefs, sexual orientation, marital status, family status or veteran status.