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escarpment live oak, live oak, plateau oak, Texas live oak

British oak, chêne pédoncule, English oak, French oak, pedunculate oak

Habit Trees, sometimes shrubs, subevergreen, trees to 25 m, shrubs often forming large clonal stands. Trees, deciduous, to 30 m. Bark light gray, scaly.
Bark

dark brown or black, scaly.

Twigs

light gray, 1.5-3 mm diam., tomentulose, tomentulum often persistent in age.

brown, 2-3 mm diam., glabrous.

Buds

reddish or dark brown, subglobose or ovate, 1.5-3 mm;

scale margins glabrous or puberulent.

dark brown, ovoid, distally obtuse, 2-3 mm, glabrous.

Leaves

blade oblong-elliptic to narrowly ovate or lanceolate, sometimes obovate, ± planar, (10-)35-90(-150) × (15-)20-40(-85) mm, base rounded to truncate or cordate, rarely cuneate, margins minutely revolute or flat, entire or irregularly 1-3 toothed on each side, teeth mucronate (rarely spinose in suckers or juveniles), secondary veins obscure, 8-10 on each side, apex obtuse-rounded or acute;

surfaces abaxially whitish or glaucous, densely covered with minute, appressed, fused-stellate hairs, light green and glabrate in shade leaves, adaxially dark or light green, glossy, glabrous or with minute, scattered, stellate hairs.

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.

Acorns

1-3, on peduncle 3-30 mm;

cup funnel-shaped, hemispheric, or deeply goblet-shaped, 8-15 mm deep × 6-12(-15) mm wide, base often constricted, scales whitish or grayish, thickened basally, keeled, acute-attenuate, tomentulose, tips reddish, glabrous or puberulent;

nut dark brown, often with light brown longitudinal stripes, subfusiform and acute to narrowly barrel-shaped, rarely distally rounded, (17-)20-30(-33) × 8-15 mm, glabrous.

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.

Cotyledons

connate.

distinct.

2n

= 24.

Quercus fusiformis

Quercus robur

Phenology Flowering spring. Flowering spring.
Habitat Hills, grasslands, scrublands, open woodlands, oak-juniper woodland, and margins of thorn scrub, often on limestone or deep calcareous loams, sometimes on granular sand or gravel Roadsides, pastures, forest margins and woodlands
Elevation 0-1200 m (0-3900 ft) 0-1000 m (0-3300 ft)
Distribution
from FNA
OK; TX; Mexico (Coahuila, Nuevo León, and Tamaulipas)
[WildflowerSearch map]
[BONAP county map]
from FNA
BC; NB; NS; PE [Introduced from Europe]
[WildflowerSearch map]
[BONAP county map]
Discussion

The difficulty in distinguishing Texas populations of Quercus fusiformis from Q. virginiana is reflected in a variety of taxonomic treatments, including reducing Q. fusiformis to varietal rank under Q. virginiana. The latter disposition is problematic, however, because Q. fusiformis in northeastern Mexico is amply distinct from Q. virginiana and appears to be more closely related to Q. brandegei Goldmann, an endemic of Baja California, Mexico. Thus, here we assume that the intergradation of Q. virginiana and Q. fusiformis is a result of secondary contact, and is not primary clinal variation. Under this interpretation, Q. virginiana in typical form extends into Texas only as far west as the Brazos River drainage along the coast from there to the escarpment of the Edwards Plateau; most populations elsewhere are either intermediate between the two species or show greater affinity with Q. fusiformis. On the Edwards Plateau, the live oak populations are small trees forming rhizomatous copses (shinneries) and having mostly acute acorns.

Populations of live oak on deep sands in south Texas differ from typical Quercus fusiformis in having broader, more rounded leaves, often with the secondary veins somewhat impressed abaxially, and relatively blunt, barrel-shaped acorns. These characteristics suggest introgresion from the Mexican-Central American species Q. oleoides Schlechtendal & Chamisso, which in its typical form reaches north only as far as southern Tamaulipas, Mexico. The name Q. oleoides var. quaterna C. H. Muller has been applied to what is apparently a shrub form of one of these Q. fusiformis × Q. oleoides hybrids.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

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.)

Source FNA vol. 3. FNA vol. 3.
Parent taxa Fagaceae > Quercus > sect. Quercus Fagaceae > Quercus > sect. Quercus
Sibling taxa
Q. acerifolia, Q. agrifolia, Q. ajoensis, Q. alba, Q. arizonica, Q. arkansana, Q. austrina, Q. berberidifolia, Q. bicolor, Q. boyntonii, Q. buckleyi, Q. carmenensis, Q. chapmanii, Q. chihuahuensis, Q. chrysolepis, Q. coccinea, Q. cornelius-mulleri, Q. depressipes, Q. douglasii, Q. dumosa, Q. durata, Q. ellipsoidalis, Q. emoryi, Q. engelmannii, Q. falcata, Q. gambelii, Q. garryana, Q. geminata, Q. georgiana, Q. graciliformis, Q. gravesii, Q. grisea, Q. havardii, Q. hemisphaerica, Q. hinckleyi, Q. hypoleucoides, Q. ilicifolia, Q. imbricaria, Q. incana, Q. inopina, Q. intricata, Q. john-tuckeri, Q. kelloggii, Q. laceyi, Q. laevis, Q. laurifolia, Q. lobata, Q. lyrata, Q. macrocarpa, Q. margarettae, Q. marilandica, Q. michauxii, Q. minima, Q. mohriana, Q. montana, Q. muehlenbergii, Q. myrtifolia, Q. nigra, Q. oblongifolia, Q. oglethorpensis, Q. pacifica, Q. pagoda, Q. palmeri, Q. palustris, Q. phellos, Q. polymorpha, Q. prinoides, Q. pumila, Q. pungens, Q. robur, Q. robusta, Q. rubra, Q. rugosa, Q. sadleriana, Q. shumardii, Q. similis, Q. sinuata, Q. stellata, Q. tardifolia, Q. texana, Q. tomentella, Q. toumeyi, Q. turbinella, Q. vacciniifolia, Q. vaseyana, Q. velutina, Q. viminea, Q. virginiana, Q. wislizenii
Q. acerifolia, Q. agrifolia, Q. ajoensis, Q. alba, Q. arizonica, Q. arkansana, Q. austrina, Q. berberidifolia, Q. bicolor, Q. boyntonii, Q. buckleyi, Q. carmenensis, Q. chapmanii, Q. chihuahuensis, Q. chrysolepis, Q. coccinea, Q. cornelius-mulleri, Q. depressipes, Q. douglasii, Q. dumosa, Q. durata, Q. ellipsoidalis, Q. emoryi, Q. engelmannii, Q. falcata, Q. fusiformis, Q. gambelii, Q. garryana, Q. geminata, Q. georgiana, Q. graciliformis, Q. gravesii, Q. grisea, Q. havardii, Q. hemisphaerica, Q. hinckleyi, Q. hypoleucoides, Q. ilicifolia, Q. imbricaria, Q. incana, Q. inopina, Q. intricata, Q. john-tuckeri, Q. kelloggii, Q. laceyi, Q. laevis, Q. laurifolia, Q. lobata, Q. lyrata, Q. macrocarpa, Q. margarettae, Q. marilandica, Q. michauxii, Q. minima, Q. mohriana, Q. montana, Q. muehlenbergii, Q. myrtifolia, Q. nigra, Q. oblongifolia, Q. oglethorpensis, Q. pacifica, Q. pagoda, Q. palmeri, Q. palustris, Q. phellos, Q. polymorpha, Q. prinoides, Q. pumila, Q. pungens, Q. robusta, Q. rubra, Q. rugosa, Q. sadleriana, Q. shumardii, Q. similis, Q. sinuata, Q. stellata, Q. tardifolia, Q. texana, Q. tomentella, Q. toumeyi, Q. turbinella, Q. vacciniifolia, Q. vaseyana, Q. velutina, Q. viminea, Q. virginiana, Q. wislizenii
Synonyms Q. virginiana var. fusiformis Q. pedunculata
Name authority Small: Bull. Torrey Bot. Club 28: 357. (1901) Linnaeus: Sp. Pl. 2: 996. (1753)
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