Quercus hypoleucoides |
Quercus berberidifolia |
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silverleaf oak |
California scrub oak, inland scrub oak, scrub oak |
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Habit | Trees or shrubs, evergreen, to 10 m. Bark black, deeply furrowed. | Shrubs, subevergreen, 1-2(-4) m. Bark gray, scaly. |
Twigs | dark reddish brown, 1.5-3 mm diam., pubescent. |
gray, yellowish, rarely reddish, 1-3 mm diam. |
Buds | reddish brown, globose or ovoid, 2-3 mm, minutely puberulent. |
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Leaves | blade narrowly ovate to ovate or elliptic, 45-120 × 15-40 mm, base cuneate to rounded, margins strongly revolute, entire or spinose with up to 11 awns, apex acute to attenuate; surfaces abaxially densely tawny- or white-tomentose, adaxially noticeably rugose, glabrous. |
blade bicolored, obovate, elliptic, occasionally subrotund, planar or moderately convex, (10-)15-30 × (8-)10-20 mm, base truncate or rounded-attenuate, rarely cuneate, margins irregularly toothed and spinose, often sublobate, rarely entire, secondary veins (3-)4-7 on each side, apex broadly rounded or acute; surfaces abaxially waxy, light green or glaucous, with scattered minute, appressed, (4-)8(-10)-rayed hairs less than 0.2 mm diam. and sparse to dense yellowish, glandular hairs, adaxially glossy or dull green, glabrous or glabrate. |
Acorns | annual or biennial; cup deeply saucer- or cup-shaped, 4.5-7 mm high × 6-13 mm wide, covering 1/3 nut or less, outer surface pubescent to sparsely puberulent, inner surface pubescent to floccose, scales appressed, blunt; nut ellipsoid to oblong, 8-16 × 5-10 mm, glabrous, scar diam. 2.5-5.5 mm. |
solitary or paired, subsessile; cup hemispheric or turbinate, rarely shallowly cup-shaped, rim thick, 8-15 mm deep × 15-20(-22) mm wide, enclosing to 1/2 nut, scales reddish or yellowish, usually strongly, irregularly tuberculate, puberulent or canescent; nut light to dark brown, ovoid, ellipsoid, or barrel-shaped, (10-)15-30 × (8-)10-20 mm, apex rounded, glabrous at maturity. |
Cotyledons | distinct. |
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Terminal | buds light chestnut brown, ovoid, 2.5-4.5 mm, glabrous except for ciliate scale margins, occasionally with tuft of hairs at apex. |
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Quercus hypoleucoides |
Quercus berberidifolia |
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Phenology | Flowering spring. | Flowering spring. |
Habitat | Common in moist canyons and on ridges | Chaparral, margins of coastal sage scrub |
Elevation | 1500-2700 m (4900-8900 ft) | 100-1800 m (300-5900 ft) |
Distribution |
AZ; NM; TX; n Mexico
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CA
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Discussion | Quercus hypoleucoides reportedly hybridizes with Q. gravesii (Q. ×inconstans E. J. Palmer [= Q. livermorensis C. H. Muller]) (see C. H. Muller 1951). Several specimens from Pima County, Arizona, fall outside the range of typical Q. hypoleucoides, suggesting hybridization with the Mexican Q. mcvaughii Spellenberg (R. Spellenberg 1992). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The name Quercus dumosa (see species treatment no. 72) has often been applied to this species. Quercus berberidifolia is the most common scrub oak of central and southern California, mostly at midelevations in the Coast Ranges. In central California it is replaced in drier interior habitats by Q. john-tuckeri, and south of the transverse ranges by Q. cornelius-mulleri. From Santa Barbara south, it does not descend to the low elevation coastal sites typical of Q. dumosa in the strict sense. Quercus berberidifolia hybridizes with numerous other white oaks of California. In southern California, putative hybrids with Q. john-tuckeri are noticeable in the mountains above Ventura and on the north slope of the Tehachapi Mountains. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 3. | FNA vol. 3. |
Parent taxa | Fagaceae > Quercus > sect. Lobatae | Fagaceae > Quercus > sect. Quercus |
Sibling taxa | ||
Synonyms | Q. hypoleuca | Q. agrifolia var. berberidifolia, Q. dumosa var. munita |
Name authority | A. Camus: Bull. Mus. Natl. Hist. Nat., sér. 2, 4: 124. (1932) | Liebmann: Overs. Kongel. Danske Vidensk. Selsk. Forh. Medlemmers Arbeider 1854: 172. (1854) |
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