Apple-and-thorn skeletonizer
Choreutis pariana
92 host plants
Last updated
In mid-summer you will spot groups of small yellowish-green larvae skeletonizing leaves on serviceberry, hawthorn, birch, and other plants, leaving vein structure intact. Damaged foliage looks lacy and translucent. These sawfly larvae feed in clusters on upper surfaces, with affected branches appearing scorched in sunny, warm conditions.
Hand-pick leaf clusters with visible larvae and destroy them; works well on smaller ornamental plants. Prune infested branch tips if damage is severe. Encourage parasitic wasps and predatory beetles by avoiding broad-spectrum insecticides. Apply insecticidal soap directly to larvae in early July before they pupate. Cosmetic pest; plants recover completely after defoliation.
Quick Reference
The apple-and-thorn skeletonizer is a yellow-green caterpillar with small black spots. As a young caterpillar it feeds on the underside of leaves. More mature caterpillars move to the upper surface of the leaf, use silk to tie the edges of the leaf together near the base, and feed inside the tent-like structure. Leaves are skeletonized, with all tissues eaten away except veins and the lower leaf surface. Skeletonized leaves turn brown and drop. The feeding caterpillars produce large quantities of webbing and frass (excrement). The adult apple-and-thorn skeletonizer is a small dark-brown moth.
Cultural Controls
- There are many natural enemies of this pest.
- Avoid broad-spectrum sprays that would disrupt biological control.
- Larvae and pupae are easily removed from rolled leaves.
- Remove heavily infested twigs.
- Management-