Thompson's sawfly

Systematic position: Thompson's sawfly (Tenthredo thompsoni) is a member of the order Hymenoptera and the family Tenthredinidae. This species is part of the diverse Tenthredo genus, which includes numerous insects known for their larval stage feeding habits on vegetation.

Affected crops: This pest primarily targets a variety of deciduous trees and shrubs. In agricultural and horticultural environments, it can be found on fruit-bearing trees such as apples and pears, as well as on various ornamental plants that provide suitable food sources for the larvae during their growth stages.

Biology and lifecycle: The lifecycle of Tenthredo thompsoni consists of four distinct stages: egg, larva, pupa, and adult. Females use their specialized saw-like ovipositor to deposit eggs inside leaf tissues. Larvae emerge after a short period and begin feeding voraciously. Once the larval stage is complete, they descend to the soil to form cocoons and undergo pupation.

Damage and pest status: The damage is caused by the larval stage, which consumes leaves. Initially, the damage appears as small holes or notches on the leaf margins, but as larvae grow, they can defoliate large portions of the plant. Significant infestations can lead to reduced photosynthetic capacity, weakening the tree's vigor and negatively impacting fruit yield or decorative quality.

Control measures: Integrated Pest Management (IPM) is recommended for controlling this sawfly.

• Regular visual inspection of foliage during the spring and early summer.
• Tilling the soil beneath host plants in late autumn to disrupt the pupation sites.
• Removal and destruction of leaves containing egg clusters or young larvae.
• Application of targeted insecticides if infestation levels exceed economic thresholds.
• Fostering populations of natural predators like parasitic wasps and predatory birds.