Blue Oak
Quercus douglasii
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Fagaceae
- Genus:
- Quercus
- Species:
- Quercus douglasii
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Tree
- Height:
- More than 40 ft
- Light Requirements:
- Full Sun
- Drought Tolerance:
- High
- Bloom Months:
- mar, apr, may
- Bloom Colors:
- Yellow
Native Range
United States: California
Keystone Species Ranking
- Caterpillar Keystone:
- ★☆☆☆☆ Based on number of butterfly and moth species using this genus as host plant (Source: National Wildlife Federation)
Host Plant for Caterpillars
Acrobasis comptella, Aristotelia urbaurea, California oakworm (Phryganidia californica), Caloptilia sp., Cameraria lobatiella, Cameraria pentekes, Cameraria serpentinensis, Cameraria temblorensis, Chionodes formosella, Chionodes occidentella, Chionodes raspyon, Chionodes trichostola, Coleophora querciella, Decodes fragariana, Dyseriocrania auricyanea, Epinotia emarginana, Evippe laudatella, Feralia februalis, fruit-tree leafroller (Archips argyrospila), Pacific tent caterpillar (Malacosoma constricta), Rhodophaea fria, Telphusa sedulitella, Xenolechia querciphaga, Gold-hunter's hairstreak (Satyrium auretorum), Mournful Duskywing (Erynnis tristis)
Soil Requirements
- Soil Type:
- rocky, well-drained, nutrient-poor soil
- pH:
- 5.5 - 7.5 (slightly acidic to neutral)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- Thrives in foothill regions with minimal water availability.
Germination Information
Pre-treatment: None required
Establishment: Q. douglasii is found on dry rocky slopes from Los Angeles county north to the Sacramento valley, California.
Source: npn.rngr.net