Tent caterpillars

The “tents” built by these caterpillars are silk shelters where they develop in groups. There, they are protected from parasites (flies and wasps), predators (birds) and inclement weather. Caterpillars also eat the leaves on the inside walls of these tents.

Some tents are like a nest made of leaves and silk, while others form a sort of silk carpet that the caterpillars never leave. The carpet is woven onto the trunk or the branches.

Tents can be seen on affected plants from May to September. However, the tents at the beginning and the end of the summer are not built by the same species. In Quebec, five species of tent caterpillars attack several species of indigenous or ornamental trees. Among them are the forest tent caterpillar, the Eastern tent caterpillar and the ugly nest caterpillar.

The best way to get these defoliators out of our trees is to submerge the tent containing the caterpillars in a bucket of soapy water. In the springtime, a dormancy oil can be used to destroy eggs that spent the winter in the tree’s branches or under its bark.