Are you seeing these caterpillars on your trees or hiding underneath things left lying around the yard? They are spongy moth caterpillars (formerly known as gypsy moth) that are busy eating and getting bigger and bigger until they get ready to change into their adult moth form. The spongy moth has escalated into one of the most important insect pests of forest and shade trees in the eastern United States. They have moved steadily westward ever since their introduction in the late 1800s, reaching Wisconsin in the late 1980s.
Right now is the time to be “crushing and brushing.”
Adult spongy moths appear within two weeks. Adult female spongy moths (pale colored) have limited mobility and can also be crushed or brushed into a container in soapy water. Since each female can easily lay upwards of 1,000 eggs, eliminating adult female moths could help prevent future problems!