Azalea sawfly

In summer you will observe irregularly shaped holes in rhododendron leaves as if chewed by larger insects, but the culprit is pale greenish larvae (sawfly) about 1/2 inch long clustered on foliage. These larvae skeletonize leaves or create shot-hole damage; heavy infestations can defoliate entire branches.

Manually remove visible larvae clusters by hand-picking on small to medium shrubs. Prune off heavily infested branches to reduce populations. Encourage parasitoid wasps and predatory beetles by avoiding broad-spectrum insecticides. Apply insecticidal soap when you first notice larvae; organic spinosad provides alternatives. Pest rarely causes long-term damage; plants recover after defoliation.