Birch sawfly

Systematic position: The birch sawfly (Latin: Cimbex femorata) belongs to the order Hymenoptera and the family Cimbicidae. It is one of the largest sawfly species in Europe. Despite its hornet-like appearance, it is harmless to humans as it lacks a stinger.

Host plants: The primary host is the birch tree (Betula). However, the larvae can also feed on the leaves of other deciduous trees such as alder, willow, poplar, and lime. They are most commonly found in forest edges, parks, and tree plantations.

Biology and life cycle: The species has a univoltine life cycle, meaning one generation per year. Mature larvae overwinter in dense cocoons within the soil or leaf litter. Pupation occurs in the spring, and adults emerge in early summer. Females lay eggs by inserting them into leaf tissues, after which the larvae hatch and begin their feeding cycle.

Damage and harmfulness: The larvae (false caterpillars) are responsible for the damage. Initially, they create small holes in the foliage, but as they grow, they consume entire leaves, leaving only the primary veins. In cases of massive infestation, the sawfly can cause significant defoliation, which stresses the trees and reduces their vitality.

• Manual removal and destruction of larvae from small trees.
• Autumn soil cultivation under the canopy to destroy overwintering cocoons.
• Application of biological insecticides containing Bacillus thuringiensis.
• Chemical treatment with registered insecticides during the peak larval feeding period.
• Encouraging the presence of natural predators like birds and parasitic wasps in the environment.