Some insects have a dramatic impact on forests.
The spruce budworm is a highly destructive insect that lives in the forests of the northern United States and southern Canada. The adult stage of this insect is a greyish moth about two cm long. The female moth lays eggs in July on spruce and fir trees. The caterpillars make tiny silk cases and remain on the trees throughout the winter. In the spring the caterpillars begin to eat the new tree buds of coniferous trees, such as spruce and fir.