Ash leaf sawfly

Systematic position: The Ash leaf sawfly Macrophya punctumalbum is a member of the order Hymenoptera and the family Tenthredinidae. It is a specialized insect pest known for its larvae feeding habits on foliage, which can lead to significant aesthetic and physiological damage to host plants.

Host plants: The primary host plant for this species is the ash tree (Fraxinus species). While it primarily targets common ash, it can be found in various environments ranging from dense forest stands to urban landscape settings where ash trees are utilized for ornamental purposes.

Biology and lifecycle: The species undergoes a complete metamorphosis. Adults emerge in spring to mate and lay eggs within the leaf tissue. Upon hatching, the larvae go through several developmental stages, feeding voraciously on the foliage. Once they reach maturity, they descend to the soil to pupate and remain there until the next season.

Damage and harmfulness: The larvae are responsible for the damage, as they consume leaf tissue. Initially, small irregular holes appear, but as the larvae grow, they can consume entire leaves except for the tougher veins. Severe infestations can cause widespread defoliation, which severely taxes the tree's resources and reduces its vitality.

Control measures: Integrated Pest Management (IPM) is crucial for managing this pest.

• Early detection through visual inspection of foliage during late spring.
• Application of selective contact or systemic insecticides if population density exceeds threshold levels.
• Soil cultivation around the base of infested trees to disrupt the pupation process and reduce the next generation's emergence.
• Encouraging natural predators, such as parasitic wasps, to control the population levels naturally.