Identifying and Treating Cochineal Scale on Prickly Pear Cacti

Recognizing Cochineal Scale

A creamy white, waxy crust on prickly pear (Opuntia) pads is classic cochineal scale (Dactylopius spp.). These tiny insects hide under white fluff, feeding on plant sap. Heavy infestations weaken plants, cause yellowing, and invite secondary infections.

Treatment Options

1. Mechanical removal: Blast with strong water jet; scrub pads with soft brush and soapy water.
2. Alcohol swabs: Dab individual colonies with 70% isopropyl alcohol.
3. Horticultural oil: Apply neem oil or dormant oil spray per label (test on one pad first).
4. Systemic insecticide: For severe cases, use imidacloprid soil drench (follow label strictly).

Prevention & Monitoring

• Inspect new plants before introducing.
• Improve air circulation; avoid overhead watering.
• Encourage natural predators (ladybugs, lacewings).
• Monitor weekly during warm months.

Resources: Arizona Cactus Sales guide and University of Arizona extension publications offer detailed identification and treatment protocols.