Argid sawflies

Host plants: Argid sawflies are notorious pests that target various woody and ornamental plants. They particularly favor the Rosaceae family, including roses, as well as several fruit-bearing trees and ornamental shrubs. Their impact is most severe in landscapes where these host plants are grown in high densities.

Biology and life cycle: The lifecycle consists of four stages: egg, larva, pupa, and adult. Females use their saw-like ovipositors to insert eggs into plant tissues. The larvae that emerge are external feeders, growing rapidly as they consume foliage. Once fully developed, most species undergo pupation either in the soil or within cocoons spun on the foliage or stems.

Damage and economic impact: The damage is characterized by extensive defoliation. Larvae often feed in groups, quickly stripping a plant of its leaves, which impairs photosynthesis and overall vigor. Severe infestations can lead to stunted growth, reduced bloom quality in ornamentals, and increased susceptibility to secondary infections or winter damage.

Management strategies: Effective control involves an integrated pest management (IPM) approach. Regular monitoring for egg masses and early-instar larvae is crucial for timely intervention. When necessary, contact or systemic insecticides are applied to manage high populations. Cultural practices, such as maintaining soil health and removing debris, are also vital for prevention.

• Hand-picking larvae from small ornamental plants.
• Applying insecticidal soaps for early-stage infestations.
• Utilizing systemic pesticides during peak larval activity periods.