Coleophora laricella

Larch casebearer

Description

This is a tiny moth with a wingspan of only 10 mm and grey coloration. Its swarming season occurs in June, and females lay their eggs on larch needles. Once hatched, the larvae tunnel into the needles, hollowing them out. In September, they sever the inhabited section from the rest of the needle and attach it to a twig with a fibrous lining, where they overwinter in the created case. After winter, the larvae continue to feed, still inside the needle case, with only the front part of their body protruding to hold onto the twig or another needle. The case is also the site of pupation, which takes place in late May. Needles of damaged trees may appear bleached. This insect is a dangerous and destructive pest, mainly in mountainous areas.

Symptom

When spruce trees are damaged, they lose their green color, the needles wither, and the trees gradually die. On the twigs of the trees, there are several millimeter-sized bags in which caterpillars live.

Tree Species: Larch

Part of a plant- attacked: Leaf / Needle

Pest significance: Very harmful

Pest Category: Insects

Invasive Species: No

Present in EU: Yes