Magnolia Scale
Neolecanium cornuparvum
1 host plant
Last updated
Quick Reference
Magnolia Scale Crawler typically begins around 5765 GDD₃₂. As of June 3, 2026, Puget Sound stations range from 2435.5 to 2672.8 GDD₃₂, approximately 3092 units before the expected threshold.
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Jun 3, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 2,673 | Pre-season | Crawler | 3,092 |
| Kent / Auburn | 2,665 | Pre-season | Crawler | 3,100 |
| Seattle / UW | 2,610 | Pre-season | Crawler | 3,155 |
| Olympia / Tumwater | 2,570 | Pre-season | Crawler | 3,196 |
| Tacoma / Puyallup | 2,535 | Pre-season | Crawler | 3,230 |
| Bellingham / Whatcom | 2,533 | Pre-season | Crawler | 3,232 |
| Sequim / Rain Shadow | 2,436 | Pre-season | Crawler | 3,330 |
GDD source: UMD IPMnet Pest Predictive Calendar (Gill & Klick). Base 50°F, mid-Atlantic climate. Converted to GDD₃₂ for Western WA. About GDD₃₂ →
Mature females are among the largest scale insects in North America, reaching 1/2 inch in diameter and resembling pinkish-orange to brown hemispheres on twigs and branches. Heavy infestations produce copious honeydew that supports black sooty mold growth on foliage and surfaces beneath the tree. Severely infested branches decline and may die back; young trees are most at risk.
Cultural Controls
- Inspect new Magnolia plantings for scale before installation.
- Prune out heavily infested branches in winter and destroy.
- Conserve natural enemies; soft scales are attacked by predaceous beetles, lacewings, and parasitic wasps.
Host Plants (1)
Sources & References
Primary: PNW Insect Management Handbook
- Cornell Cooperative Extension — Magnolia Scale fact sheet