Winter moth

The Winter moth (Operophtera brumata) is a destructive pest belonging to the Geometridae family within the order Lepidoptera. It is well-known for its ability to thrive in temperate climates, causing significant economic damage to both orchards and broad-leaved forest trees across many regions.

This insect affects a wide variety of fruit trees, including apple, pear, plum, and cherry trees. In addition to cultivated plants, they frequently feed on oak, lime, and birch species. The caterpillars are highly active feeders, capable of causing widespread defoliation in late spring when food resources are most vital for tree growth.

The life cycle of the Winter moth is distinct because the adult moths emerge in late autumn or early winter. While the males possess functional wings and are strong fliers, the females are flightless and must crawl up the trunks of trees to lay their eggs in bark crevices, where they overwinter successfully even in harsh cold.

Damage caused by the larvae begins early in the season when they feed on opening buds and young leaves. The caterpillars use silk threads to tie leaves together, creating shelters where they consume the leaf tissue, leaving behind only the veins. This destruction impairs the tree's ability to produce energy, weakening it and reducing fruit quality.

Effective management strategies rely on disrupting the life cycle. Applying sticky grease bands around the trunks in autumn prevents flightless females from climbing up to lay eggs. In early spring, if infestation levels are high, targeted applications of biological or chemical insecticides can be used, alongside promoting natural predators like insectivorous birds.

• Installing sticky grease bands on tree trunks in October.
• Monitoring adult moth activity during autumn nights.
• Using biological agents like Bacillus thuringiensis.
• Encouraging wild birds and parasitic wasps in the orchard.
• Pruning and cleaning bark to reduce egg-laying sites.