Gypsy moth

Gypsy moth

What is the Gypsy moth?

The gypsy moth is an invasive forest pest from Europe that is one of the most damaging tree defoliators currently in the U.S. Aspen and oak top the list of over 500 preferred host species. Gypsy moth caterpillars feed on leaves of deciduous trees and are present in early to mid-summer.

Adult gypsy moths
Gypsy moths: female (left) and male (right)

Gypsy moth catepillars feeding on leaves.
Gypsy moth caterpillars feeding on leaves

Why are gypsy moths such a problem?

Gypsy moth identification and biology
Gypsy moth impacts

Gypsy moths in the U.S.

Introduced to the U.S. in 1869, over the following 100 years, gypsy moth spread slowly across New England—primarily through caterpillar movement. Over the next 40 years, gypsy moth quickly spread as a result of human activities (motorized vehicles and tourism). Today the area infested with gypsy moth spans across the eastern U.S. and into Wisconsin. The USDA Forest Service began a slow the spread program to help states on the advancing edge of gypsy moth infestation delay the establishment of the moth.

Gypsy moth spread in the U.S.

Gypsy moth in Minnesota

The Minnesota Department of Agriculture (MDA) has been monitoring (trapping) gypsy moth since 1970 and has successfully eradicated a number of small isolated infestations. In 2004, four Minnesota counties were added the slow the spread program because of high trap counts. In recent years, MDA has captured high numbers of male moths along the North Shore of Lake Superior. Based on moth capture rates and the presence of alternate life stages, MDA has proposed a quarantine for Cook and Lake pdf counties, likely to be put in place in July 2014.

What is Minnesota doing to manage gypsy moths?

Gypsy moth management

Gypsy moth controls include cultural, mechanical, and chemical controls; natural predators; and silvicultural practices. Unfortunately, because it's a nonnative pest, gypsy moth has few natural controls of the gypsy moth in the U.S. and none capable of preventing its eventual establishment in Minnesota. Various practices are used at different stages of population development. There are state and federal programs available at each stage to provide technical and financial assistance.

Gypsy moth management options

What can I do?

Removing gypsy moth egg massRemove gypsy moth egg masses from vehicles and belongings

You can play a major role in continuing to slow the spread of gypsy moth in Minnesota.

For more information about the MDA's gypsy moth program, call the Minnesota Department of Agriculture by calling the Arrest the Pest Hotline at or 888-545-6684.