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Compare sources for Quercus tomentella

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Field
Oaks of the World
The Sibley Guide to Trees
Common Names
Island live oak, Island oak
Channel Island Oak, Island Live Oak, Island Oak
Geographic Range

California Islands (Santa Rosa, Santa Cruz, Santa Catalina, Santa Clemente); Mexico (Guadalupe Island); 100 to 900 m;

Wild Only on 5 Southern Channel Islands

Growth Habit

6-12 m tall usually, but may reach 20 m, with trunk to 0.4-0.6 m in diameter; crown rounded with spreading branches;

Evergreen. Small tree often 30’, broad and rounded. Resembles chrysolepis in general form but has larer thicker leaves with more promonent teeth and somewhat courrgated leaf blade

Leaves

5-10 x 2.5-5 cm; evergreen; stiff; leathery; elliptic or ovate, sometimes slightly oblong; apex pointed to attenuate; base obtuse to rounded, cordate or not; margin slightly thickened, strongly revolute, cartilaginous, entire, or crenate-dentate with 3-7 pairs of teeth; glossy dark green or yellowish green above, hairless or with some scattered stalkless trichomes, mainly at base of midvein; greyish, densely tomentose beneath (hence the specific name), with scattered, sessile stellate hairs and simple ones along midvein; 8-12 conspicuous, parallel vein pairs, strongly impressed adaxially, raised beneath; petiole 3-10 mm long, thick, flattened above, with rusty hairs;

  • 3 1/2”
  • leathery brittle with rusty hairs
  • wavy, strongly curled under
  • prominent parallel veins
  • underleaf brownish hairy
Fruits (Acorns)

acorn 2.5-3 cm long; solitary or paired; apex rounded; cup sessile or with a 0.8-1.3 cm long peduncle, hairy inside and outside, with warty scales, enclosing 1/3 to 1/2 of nut; maturing in 2 years from August to October;

-1 1/4”

  • cup shallow, pale, wooly, solitary
Flowers

in April-May; staminate flowers pubescent, on 5-8 cm long catkins; female inflorescences few-flowered;

Twigs

hairy to 2nd year

Hardiness & Habitat

not quite hardy (zone 8); all types of soils without limestone;

Rare and local in lower parts of steep canyons.

Additional Information

– A.Camus : n° 294; – Sub-genus Quercus, section Protobalanus; – Discovered in Guadalupe Island in 1875; – Threatened (IUCN Red List Category : EN). – Resembles Q. agrifolia (which has convex leaves, secondary veins not so conspicuous), and Q. parvula (which has stalked acorns);

Hybridizes with chrysolepis on several islands. chrysolepis absent on Santa Rosa, usually found in lower elevations.
Very rare in cultivation, but cultivated trees can grow taller than in the wild