Cherry web-spinning sawfly

Systematic position: The cherry web-spinning sawfly Neurotoma iridescens belongs to the order Hymenoptera and the family Pamphiliidae. It is recognized as a significant pest in orchards, known for its unique behavior of creating silk nests on host plants.

Affected crops: This pest primarily targets cherry and sweet cherry trees. However, it can also infest other stone fruit species, including plums. Its presence is most noticeable in home gardens and commercial orchards where proper monitoring is neglected.

Biology and life cycle: The life cycle is univoltine, meaning there is one generation per year. Adults emerge in spring to mate and lay eggs on the leaves. The larvae are communal, immediately weaving silk webs upon hatching. These webs serve as protection while they feed, and larvae remain inside until they are ready to pupate in the soil.

Damage patterns and economic importance: Larvae feed gregariously on the leaves, causing skeletonization and extensive tissue loss. Severe infestations result in the total defoliation of branches or entire trees. This weakens the tree significantly, affecting growth, fruit quality, and long-term health of the orchard.

• Mechanical removal and destruction of silk nests during regular field inspections.
• Application of contact or systemic insecticides during the early larval stage.
• Tilling the soil under the tree canopy in late summer to expose pupae to predators.
• Encouraging natural predators such as birds and parasitic wasps in the orchard ecosystem.