Spongy Moth Insect Pest Impacts Preserve

If you’ve walked the trails in the Preserve recently, especially around Frautschi Point, Tent Colony, and Raymer’s Cove, you may have noticed buff-colored, suede-like patches several inches in size on tree trunks. These are the egg masses of spongy moth (Lymantria dispar), formerly know as gypsy moth*. Spongy moth is an invasive, non-native insect with larvae that feed voraciously on the foliage of many North American plants. While spongy moth may not kill a tree outright, repeated defoliation can weaken trees, resulting in greater susceptibility to disease and other insect pests.

PJ Liesch, Director of the UW-Madison Insect Diagnostic Lab said last year’s drought conditions helped spongy moth populations increase statewide, including in the Lakeshore Nature Preserve.

Infestations within forested natural areas are a challenge, but actions can be taken to protect urban/landscape trees. For more information visit gypsymoth.wi.gov.

*The change in name was recently made by scientists because the word ‘gypsy’ is an ethnic slur and the former common name equated people with insects. For more information on the name change, visit the Entomological Society of America website.
Spongy moth is named for its buff-colored, suede-like egg masses.
Many egg masses are located high in trees like this black cherry near Frautschi Point.