Treating Cycad Scale on Sago Palms in Houston

Aulacaspis Scale on Cycas revoluta: Houston-Area Protocol

Two sagos with white scale (Aulacaspis yasumatsui) and yellowing, near begonias: horticultural oil + systemic drench, timed correctly.

Treatment Plan

1. Horticultural oil: "Ultra-Fine Oil" or "Organocide" (oil + fungicide). Apply late afternoon (avoid leaf burn). Coat all surfaces—undersides, trunk, crown. Let sit overnight. Rinse next morning with strong spray. Repeat 3× at 2-week intervals.
2. Sticker/spreader: Add to oil per label—improves coverage on waxy scale.
3. Systemic drench: Bayer Advanced Tree & Shrub (imidacloprid) or comparable. Apply when sago pushes new growth (spring/early summer)—roots must be active to translocate. Drench soil per label.
4. Begonia safety: Oil safe if not sprayed directly on them. Cover or avoid drift.

Critical Persistence

• Scale has multiple overlapping generations
• Oil kills only contacted crawlers/adults
• Systemic kills feeders on new growth
• Monthly monitoring + spot treatment indefinitely

Florida Reality

Many Florida sagos lost to this pest. Consistency wins. If plant declines severely, consider replacement with scale-resistant cycads (Dioon, Ceratozamia).