San Diego Management & Monitoring Program


Nuttall's scrub oak
Quercus dumosa


Kingdom Phylum Subphylum Class Order Suborder Family

Current distribution rangewide

South coast and Peninsular Ranges of Santa Barbara, Ventura, Los Angeles, Orange, and San Diego County, as well as Baja California, Mexico [1, 2].


Known Populations in San Diego County

Thirty occurrences on Conserved Lands in Mus 1 (Cabrillo National Monument), 2 (Florida Canyon, Rose Canyon Open Space, Soledad Natural Park, Switzer Canyon, Tecolote Canyon Natural Park, Tierra Santa Open Space), 3 (Otay Ranch Preserve, San Diego National Wildlife Refuge), 4 (Elliot Reserve, International University Open Space, Mission Trails Regional Park, Sycamore Canyon), 6 (Black Mountain Open Space Park, Carmel Valley Restoration and Enhancement Project, Del Mar Heights, Del Mar Mesa Open Space, Faraday Open Space, Los Penasquitos Canyon Preserve, Lusardi Creek Preserve, Manchester Mitigation Bank, Overlook Park, Rancho La Costa Habitat Conservation Area, San Elijo Reserve Ecological Reserve, the Crosby at Rancho Sante Fe, Torrey Pines State Natural Reserve ), 7 (Torrey Pines State Natural Reserve), and 10 (Santa Ysabel West Open Space Preserve).


List status

None [2].


Habitat affinities

Sandy, clay loam of closed-cone coniferous forest, chaparral, and coastal scrub [2]. Elevation range is 15-400 meters [1].


Taxonomy and genetics

Fagaceae family [2].


Life history demography

Perennial evergreen shrub to tree [2]. Lifespan up to 100 years old [3, 4]. Good recruitment requires a year of abundant rain on chaparral that has not burned for 50 years or more [7, 9]. Slow growing [3].


Seasonal phenology

Bloom period is February-August [2].


Pollination seed dispersal

Acorns mature in 1 year [5, 6] and rain stimulates germination [7]. Acorns dispersed by granivorous animals or fall near the tree [7, 9, 10]. Monoecious plant [8].


Threats

Development, fire suppression, and vegetation/fuels management [2]. Possibly threatened by hybridization with Q. berberidifolia.


Special considerations:

Hybridizes with Q. berberidifolia, Q. lobata, and Q. dumosa ssp. kinseliae [1]. Stump sprouts after fire and cutting [8]. Viable acorns can be picked 1.5-2 months before maturity, and after proper drying, can be stored for 1 year at 3-4 degree Celsius [4].


Nuttall's scrub oak sources