Pear stem sawfly

The pear stem sawfly (Latin: Janus kashivorus) is a dangerous pest of fruit crops, belonging to the order Hymenoptera and the family Cephidae. This species specializes in damaging young shoots, which leads to a significant reduction in yields and hinders the overall growth of the trees.

The main host plant for this species is the pear tree. Adult insects lay eggs into the tissues of young, non-lignified shoots, creating sites for larval development inside the plant. Affected areas often cease to develop, which disrupts the normal sap flow within the tree.

The life cycle includes the stages of imago, egg, larva, and pupa. Larvae overwinter in the lower part of the damaged shoots or within the wood, where they pupate in the spring. The emergence of adults typically coincides with the beginning of the pear's growing season, making control measures particularly urgent during the spring months.

The damage is characterized by the wilting and subsequent drying out of shoot tips. As the larva tunnels inside the shoot, it creates galleries that cause the shoot to die off. Externally, this appears as the twisting or snapping of the tip, inside which one can find the larva or traces of its activity.

Control measures include a combination of agrotechnical and chemical approaches:

• Timely sanitary pruning and destruction of infested shoots before the larvae emerge.
• Attracting natural biological control agents to the orchard.
• Spraying trees with insecticides during the period of mass adult flight.
• Maintaining proper cultural practices to increase tree resilience.