Whitefly

Whiteflies are tiny, moth-like insects covered with white powdery wax, clustering on the undersides of leaves. You will see yellowing and stunting on Ceanothus and other ornamental hosts in western Washington. Nymphs are flattened, oval, and transparent. Heavy infestations produce copious honeydew, which promotes sooty mold and attracts ants. Damage is primarily cosmetic.

Spray insecticidal soap or horticultural oil on the underside of infested foliage every seven to ten days until populations decline. Encourage natural enemies including parasitoid wasps (Encarsia species) by avoiding broad-spectrum pesticides. Yellow sticky traps monitor population levels. For severe infestations, spinosad provides rapid knockdown.