California Black Oak
Quercus kelloggii
Fagaceae · broadleaf deciduous tree · native
Last updated
Quercus kelloggii (Fagaceae) is a large deciduous oak native to the mountains of Oregon and California. It grows 40 to 80 feet tall with a broad, rounded crown. The deeply lobed, bristle-tipped leaves place it in the red oak group (section Lobatae). Fall color is yellow to russet.
California black oak grows in full sun on well-drained soils at elevations of 1,000 to 8,000 feet. It is adapted to the dry-summer Mediterranean climate of its range. Acorns were a primary food staple for indigenous peoples of California and southern Oregon. Hardy in Zones 7a to 8b.
Quick Facts
Primary Spore Release
Spring Canker Activation
Spring Spore Germination and Infection
Spore Release (Fall & Spring Rains)
+ 4 more — see full disease and pest lists below
Phenological Calendar
As of May 14, 2026, Puget Sound stations range from 1926.1 to 2121.1 GDD₃₂. California Black Oak typically reaches 'leaf emergence' at 3533 GDD₃₂, predicted around Jul 6.
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of May 14, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 2,121 | Pre-season | 'Leaf emergence' | 1,412 |
| Kent / Auburn | 2,113 | Pre-season | 'Leaf emergence' | 1,420 |
| Seattle / UW | 2,085 | Pre-season | 'Leaf emergence' | 1,448 |
| Olympia / Tumwater | 2,047 | Pre-season | 'Leaf emergence' | 1,486 |
| Tacoma / Puyallup | 2,016 | Pre-season | 'Leaf emergence' | 1,517 |
| Bellingham / Whatcom | 1,994 | Pre-season | 'Leaf emergence' | 1,539 |
| Sequim / Rain Shadow | 1,926 | Pre-season | 'Leaf emergence' | 1,607 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ○ 'Leaf emergence' BBCH '11' NEXT | 3533 | '' est. Jul 6 (avg) |
Source: 'NPN citizen science observations (WA+OR), n=16, median. services.usanpn.org' About GDD₃₂ →
Season tracker for Kent / Auburn as of May 14, 2026. Predicted dates use 16-day weather forecast through May 30, 2026, then climate normals.