Sawflies

The genus Hoplocampa belongs to the family Tenthredinidae, order Hymenoptera. These insects are significant pests of fruit crops, widely recognized for their ability to infest developing buds and fruitlets, leading to substantial yield losses in orchards across temperate regions.

These pests primarily target rosaceous fruits, with the apple sawfly (Hoplocampa testudinea) and the plum sawfly (Hoplocampa flava) being the most economically important species. Each species is highly host-specific, timing its life cycle to coincide with the flowering stage of its preferred host plant.

The biology of Hoplocampa involves a single generation per year. They overwinter as mature larvae inside earthen cocoons within the soil. Adult sawflies emerge in the spring, coinciding with the blossom period, when females utilize their saw-like ovipositors to insert eggs into the sepals or the base of the flower.

The larvae are the primary damaging stage. Upon hatching, they burrow into the developing fruitlet, often creating winding tunnels filled with dark frass. Infested fruitlets usually wither and drop prematurely. A single larva is capable of destroying several fruitlets before completing its development, which can result in severe thinning or total crop failure.

• Cultivation of soil under tree canopies to disrupt overwintering sites.
• Sanitation by collecting and disposing of infested fruit drops.
• Use of white sticky traps to monitor adult flight and reduce populations.
• Application of selective insecticides shortly after petal fall to target young larvae.

Effective management requires a combination of cultural practices and timely chemical intervention. Monitoring is key; orchardists should deploy traps before the bloom starts. Chemical control is most effective immediately after petal fall, before the larvae burrow deep into the fruitlets, where they become protected from contact insecticides.