Larch longhorn beetle

The Larch longhorn beetle (Tetropium gabrieli) is a wood-boring insect belonging to the order Coleoptera and the family Cerambycidae. This species is specifically associated with the genus Larix (larch trees), acting as a significant primary or secondary pest in forestry.

This pest mainly attacks weakened, stressed, or recently felled trees. Vulnerability in larch stands is often increased by external factors such as prolonged droughts, forest fires, or windfall events that compromise the tree's defense mechanisms against insect colonization.

The biological cycle begins with adult beetles emerging in late spring. After mating, females lay eggs into crevices in the bark. Upon hatching, the larvae bore into the inner bark and cambium layers, creating intricate galleries. They eventually tunnel deeper into the sapwood to pupate, spending a significant portion of their development cycle within the wood structure.

The damage caused by the larvae is severe as they destroy the cambium, effectively disrupting the flow of water and nutrients within the tree. This leads to the rapid decline and death of the host. Infested trees are often identified by the presence of wood dust (frass) on the bark and oval exit holes left by emerging adults.

Effective management strategies include:

• timely sanitation logging to remove infested trees;
• prompt disposal of logging residues to prevent beetle reproduction;
• monitoring populations using attractant traps during the flight season;
• promoting forest health and site-specific silvicultural practices.