Large Aspen Tortix Life Cycle and Description

The large aspen tortix is a forest tent caterpillar that becomes a pest to some parts of the world. The caterpillars find homes in the willow, alder, white birch, and trembling aspens. They are one of the shortest living pests, since they are prey to numerous predators and parasites.

Lifecycle of the Large Aspen Tortix

You’ll find the larvae of the creatures crawling around the base of the host trees in early May. They want to mine before buds option, with pupation occurring by mid-June. By late June and into early Augusts, the caterpillars turn into moths and lay their eggs.
Trees affected will have a silken tent cover around the leaves. This is a protective layer for the eggs. The affected trees will also only tend to have a few leaves left on the crowns, where the larvae pupate. You’ll likely see a range of rolled leaves, with some black egg clusters around.
Many large aspen tortix won’t make it to moth stage. They are easily killed by disease, but are popular prey for birds and larger insects.

Large Aspen Tortix Description

When larvae first hatch, they are green and translucent and have to feed on some of the died leaves that the older larvae have created. The young larvae have a yellow/green colouring to their bodies. As they mature, they turn dark green to black, with brown legs and heads. They reach to about 20mm in length before cocooning and turning into moths.
The wingspan of a moth is 25-35mm, with females larger than the males. You’ll notice the moths as they are about average size with smoky grey colouring to the back wings and a browny/grey colouring to the front.
If you notice you have large aspen tortix, you may need help to control the population.