Raspberry sawfly

The raspberry sawfly (lat. Monophadnoides geniculatus) is a member of the Hymenoptera order, specifically the family Tenthredinidae. As a specialized agricultural pest, it primarily targets raspberry plants, although it can occasionally be found on blackberry bushes, causing significant concern for berry growers.

The primary hosts for this insect are Rubus species. The larvae of this species are foliage feeders, which means they specialize in consuming the soft leaf tissue of the host plant. If left uncontrolled, a heavy infestation can lead to severe defoliation, negatively impacting the plant's metabolic processes.

The lifecycle of this pest typically involves a single generation per year, though environmental factors may influence the timing. The insect overwinters as a larva inside a cocoon within the soil. Adult females emerge in the spring, laying their eggs within the leaf tissue, which protects the developing larvae from natural predators and environmental hazards during the early stages.

Damage caused by the raspberry sawfly starts with small holes in the leaves. As the larvae grow, their consumption rate increases significantly, leading to skeletonized leaves where only the main veins remain. This damage reduces the plant's photosynthetic capacity, leading to reduced fruit size, weaker cane growth, and lower yields in the following season.

Integrated pest management strategies for this insect include:

• Cultivating the soil around the base of the bushes in late autumn to expose overwintering cocoons to frost and predators.
• Regular monitoring of foliage during the spring to detect early signs of larvae activity.
• Hand-picking larvae on small plots or in home gardens.
• Applying selective organic or synthetic insecticides during the early larval stages when the larvae are most vulnerable.