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Eastern fox squirrel

Sciurus niger

Large tree squirrel with grizzled fur, orange-rufous underside, and bushy tail. Invasive in Bay Area; outcompetes native squirrels for acorns and tree cavities. Major oak seed disperser but transforms native forest structure.

Plants that support Eastern fox squirrel

12 plants

Bigcone Pine

Pinus coulteri

high

tree

Cache large cones for winter food; major seed disperser

Bay Area nativeKeystone species

Box-elder

Acer negundo

high

tree

Primary seed dispersal and consumption Sep-Mar; critical mast crop resource

Bay Area nativeKeystone species

California Black Oak

Quercus kelloggii

high

tree

Acorn caching and consumption Sep-Nov; important seed disperser and energy source for overwintering

Bay Area nativeKeystone species

California Sycamore

Platanus racemosa

moderate

tree

Utilizes cavities and dense canopy for den sites and shelter year-round

Bay Area native

Common sunflower

Helianthus annuus

moderate

annual

Fall seed caching; important food source for cache-building behavior

Bay Area nativeKeystone species

Interior Live Oak

Quercus wislizeni

high

tree

Acorn caching and consumption, primary fall food source

Bay Area nativeKeystone species

Knobcone Pine

Pinus attenuata

moderate

tree

Cache pine seeds; cones of Pinus attenuata are serotinous but provide seasonal seed resource

Bay Area nativeKeystone species

Pacific Poison Oak

Toxicodendron diversilobum

moderate

shrub

Where introduced in CA; fall foraging for caching

Bay Area native

Rincon Manzanita

Arctostaphylos stanfordiana ssp. decumbens

moderate

perennial herb

Cache seeds in fall when available from mature plants

Bay Area nativeKeystone species

Santa Cruz Island Oak

Quercus parvula var. shrevei

high

tree

acorn cache harvesting and consumption August-February

Bay Area nativeKeystone species

Scrub oak

Quercus berberidifolia

high

tree

Acorn caching and consumption, September through winter

Bay Area nativeKeystone species

Utah Serviceberry

Amelanchier utahensis

moderate

shrub

Late summer/early fall mast collection and consumption Jul-Sep

Bay Area nativeKeystone species