Quercus robur |
Quercus hinckleyi |
|
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British oak, chêne pédoncule, English oak, French oak, pedunculate oak |
Hinckley oak |
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Habit | Trees, deciduous, to 30 m. Bark light gray, scaly. | Shrubs, evergreen, low, to 0.75(-1.5) m, spreading rhizomatously in thickets, intricately branched. |
Bark | gray, scaly. |
|
Twigs | brown, 2-3 mm diam., glabrous. |
light brown, pruinose, becoming waxy-glaucous in 2d season, 1-1.5 mm diam., glabrous or sparsely and minutely stellate-pubescent. |
Buds | dark brown, ovoid, distally obtuse, 2-3 mm, glabrous. |
minute, subrotund, 0.5-1 mm; scales reddish brown, glabrous except for ciliate margins. |
Leaves | blade obovate to narrowly elliptic or narrowly obovate (some cultivars oblanceolate), (50-)70-150(-200) × (20-)35-85(-100) mm, base strongly cordate, often minutely revolute or folded, margins moderately to deeply lobed, lobes rounded or retuse distally, sinuses extending 1/3-7/8 distance to midrib, secondary veins arched, divergent, (3-)5-7 on each side, apex broadly rounded; surfaces abaxially light green, glabrous or sparsely pubescent, glabrous at maturity, adaxially deep green to light green or gray, dull or glossy. |
blade subrotund or rotund, to 15 × 15 mm, thick, leathery, base cordate or auriculate, margins strongly crisped with 2-3 coarse, spinescent teeth on each side, cartilaginous-thickened secondary veins obscure, apex acute or obtuse, spine-tipped; surfaces abaxially blue-green, glaucous, glabrous, microscopically markedly papillose, adaxially blue-green, glaucous, glabrous, secondary veins slightly raised on both surfaces. |
Acorns | 1-3, on very thin (1-2 mm diam.), flexuous peduncle (25-)35-65(-100) mm; cup hemispheric to deeply goblet-shaped, enclosing 1/4-1/2 nut or more, scales closely appressed, often in concentric rows, finely grayish tomentose; nut brown, ovoid, oblong, or cylindric, 15-30(-35) × 12-20 mm, glabrous. |
solitary, subsessile or on axillary peduncle to 4 mm; cup shallow, saucer-shaped, 1-3 mm deep × 10-15 mm wide, enclosing base of nut only, margin irregularly undulate, scales closely appressed, minute, basally tuberculate-thickened, glabrous except for thin ciliate margins; nut ovoid, 10-20 × 8-12 mm, glabrous. |
Cotyledons | distinct. |
distinct. |
2n | = 24. |
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Quercus robur |
Quercus hinckleyi |
|
Phenology | Flowering spring. | Flowering spring. |
Habitat | Roadsides, pastures, forest margins and woodlands | On dry desert slopes |
Elevation | 0-1000 m (0-3300 ft) | 1150-1400 m (3800-4600 ft) |
Distribution |
BC; NB; NS; PE [Introduced from Europe]
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TX; Mexico |
Discussion | Quercus robur is one of the oaks most commonly cultivated in temperate and subtropical parts of the world. In North America it is most commonly seen in the eastern and northwestern parts of the United States and and in southeastern and southwestern Canada, where it tolerates a wide array of conditions and is extremely hardy. In Washington, New Brunswick, and Nova Scotia, apparently reproducing populations persist in the wild. Elsewhere, although actual naturalization appears to be rare, Q. robur should be expected to persist around old homesites and other places of cultivation. Quercus robur most closely resembles our native species Q. alba in leaf form. In contrast with Q. alba, which has relatively long petioles (longer than 10 mm), acute leaf bases, and subsessile fruit (rarely on peduncles to 25 mm), Q. robur is easily distinguished by its shorter petioles (less than 10 mm), cordate, almost clasping, leaf bases, and fruit on long (more than 35 mm), thin peduncles. Quercus robur is one of the oaks most widely celebrated in literature; it has wood of exceptionally high quality for the manufacture of furniture, and it previously was the most important wood used in the manufacture of wooden sailing vessels in Europe. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. This species is known only from two sites in the United States, El Solitario and near Shafter, Texas. The Shafter population includes some individuals with characteristics that suggest hybridization with Quercus pungens Liebmann. These plants are larger, with more pubescent twigs and leaves, and hemispheric acorn cups to 10 mm deep. Such plants have recently been collected in adjacent Mexico. Fossil evidence from packrat middens indicates Q. hinckleyi probably had a broader distribution and was a dominant shrub between 19,000 and 9500 years ago. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 3. | FNA vol. 3. |
Parent taxa | Fagaceae > Quercus > sect. Quercus | Fagaceae > Quercus > sect. Quercus |
Sibling taxa | ||
Synonyms | Q. pedunculata | |
Name authority | Linnaeus: Sp. Pl. 2: 996. (1753) | C. H. Muller: Contr. Texas Res. Found., Bot. Stud. 1: 40. (1951) |
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