Index / Search / Quercus douglasii

§1 Plant

Quercus douglasii Hook. & Arn.

vernacular blue oak — species · Fagaceae


USDA
QUDO
GBIF
2878266
Rank
species
blue oak (Quercus douglasii)
Platephotograph · Eric ClevelandCC BY-NC source · iNaturalist ↗

§2Habit & range

Habit and range

Growth habit
Tree
Duration
Perennial
Group
Dicot
Family
Fagaceae Dumort.
Genus
Quercus
§2a

Native status, by region

  • L48 Lower 48 States Native
§2b

County-level range

· 42 counties across 1 state
Legend Native · 42 Introduced · 0 Both · 0 Hover a county for detail.

§3Cultivation specs · USDA

Recorded by the USDA Plant Materials Program.

§3a

Tolerances

Drought
High
Shade
High
Moisture use
Low
Fire
Low
Salinity
None
Anaerobic
None
CaCO₃
None
Hedging
None
§3b

Climate & soil

Cold tolerance
10 °F minimum
Frost-free days
150 min.
Precipitation
10–60 in/yr
pH range
4.5–7.5
Root depth
32 in min.
Fertility need
Low
Soil texture
coarse, medium
§3c

Form & growth

Growth form
Single Stem
Growth rate
Slow
Lifespan
Long
Mature height
60 ft
Height @ 20 y
16 ft
Foliage texture
Coarse
Foliage colour
Gray-Green
Porosity (summer)
Moderate
Porosity (winter)
Porous
Flower colour
Yellow
Fruit colour
Brown
Fire resistant
No
N fixation
None
Toxicity
None
§3d

Reproduction

Bloom period
Spring
Seed abundance
Medium
Seed begins
Summer
Seed ends
Fall
Spread rate
Slow
Stratify
No
Seeds / lb
100
Propagation
seed, bare root, container
§3e

Use & availability

Commercial availability
Contracting Only
Nursery stock
No
Browse palatability
Low
Palatable, human
Yes
Lumber
No
Fuelwood
High
Christmas tree
No

§4Counties, by state

Recorded in 42 counties across 1 state.


§5Sources & provenance

USDA PLANTS

Symbol, taxonomy, distribution, cultivation specs, native status. Public domain.

plants.usda.gov/QUDO ↗

GBIF Backbone

Canonical taxonomic identity, synonym resolution, cross-refs. CC0.

gbif.org/species/2878266 ↗

Record version

Cached and built locally. Source version on this record:

usda-plants-mt-2026-05-26

fetched 2026-05-26T20:46:58Z