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Spongy moth (Lymantria dispar)

Spongy moth Common Names: Formerly known as the Gypsy moth.

Description: Introduced to the United States in 1869 by a French scientist living in Massachusetts.

Identification: Young caterpillars are black or brown and about 1/4 in (0.6 cm) long; segmented into 11 sections, each having 2 colored spots; first 5 pairs are blue, the last 6 are red. Mature caterpillars grow to 2 1/2 in long. Adult males are grayish brown and can fly, while adult females are larger, whitish with black marks and cannot fly.

Hosts: Deciduous hardwood trees such as maple, elm, and particularly oak. Also will feed on apple, alder, birch, poplar, and willow trees. When mature it will even attack evergreens like pines and spruces.

Life Cycle: Life cycle of four stages: egg (8 mths), larva (2 mths), pupa (7-14 days), and adult; adults mate and die in 1-2 weeks. Adult females lays one egg mass that is 1.5 in (4 cm) in size and appear as tan hairs on tree trunks. Each egg cluster contains 500 - 1,200 eggs.

Impact and Damage: The larva or caterpillar is the most destructive stage. They can consume a tremendous amount of leaf material (as much as one square foot of leaves a day). At larger populations, they can completely defoliate host trees over a wide geographic area. Consistent or repeated defoliation over several years can lead to severe stress on a tree and death.

Similar species: Eastern tent Caterpillars (Malacosoma americanum) and Forest Tent Caterpillars (Malacosoma disstria) look very similar when first emerging but key characteristics tell them apart in older caterpillars.

Monitoring and rapid response: Natural predators like the white footed mouse; the fungal pathogen, Entomophaga maimaiga; Nucleopolyhedrosis virus (NPV); tiny non-stinging wasps, Ooencyrtus kuvanae; Chemical controls such as Btk, Dimilin, Gypchk, and Mimic; Mating disruption with pheromone jars.

Credits: The information provided in this factsheet was gathered from the Minnesota Department of Natural Resources.

Individual species images that appear with a number in a black box are courtesy of the network ( photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (

Common Name:

Spongy moth

Scientific Name:

Lymantria dispar