Pale green weevils

Pale green weevils, Polydrussus impressifrons, is an exotic insect that was first reported in North America in New York State in 1906. The adult weevil feeds on the leaves of many broadleaf plants from strawberries to birch trees. Large numbers have been observed in northern Minnesota for about the past five or six years. Largest numbers of adults were present in June and July, but by the last week of July only a few adults were still feeding.

Tenting in the summer

Summer time. Time to put the tent up in the backyard and camp out. Time to hang out with two to three hundred of your hairy little brothers and sisters munching on tree leaves. Just about any broadleaf tree will do because more than 100 tree species are listed as hosts of the fall webworm.

Adults of the fall webworm emerge from May to June, laying masses of several hundred eggs. Moths are white and sometimes have dark spots on the wings. Larvae are pale yellow and are covered with long hairs. The larvae construct webs or tents in the branches of trees and eat the leaves that are enclosed inside the enlarging webs. Tents become most conspicuous in late July and August. After the larvae finish feeding they drop to the ground and form cocoons where they overwinter. Because defoliation occurs late in the growing season the fall webworm is usually not considered a serious, biological problem. It's more of an aesthetic problem.

There are a number of other tent or web making caterpillars. If you want to know how to tell them apart, (and you keep old copies of this newsletter) refer back to the June 1997 issue. The feature article was titled "Webworms, tent caterpillars and other web making insects". Otherwise contact your Region Forest Health Specialist listed on the last page of the newsletter and ask for a copy of the article. The article and the entire June 1997 issue of the newsletter can also be found on the Internet at the address listed under the title on the first page of this newsletter.