Quercus nigra |
Quercus vaseyana |
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chêne gris, water oak |
sandpaper oak, Vasey oak |
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Habit | Trees, deciduous or tardily deciduous, to 30 m. Bark grayish black, fissures irregular, shallow, inner bark pinkish. | Shrubs or small trees, evergreen or subevergreen, to 10 m. Bark dark brown, furrowed and exfoliating in long strips. |
Twigs | dark red-brown, 1.5-2.5 mm diam., glabrous. |
reddish or grayish brown, 1-1.5 mm diam., short stellate-tomentose or tomentulose, later glabrate or persistently pubescent, rarely glabrous. |
Buds | dark red-brown or gray, round-ovoid, 1-1.5 mm, apex obtuse, sparsely pubescent or glabrate. |
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Leaves | blade distinctly obtrullate, rarely elliptic or merely obovate, widest near apex, 30-120(-160) × 15-60(-70) mm, base attenuate or cuneate, rarely rounded, margins entire with 1 apical awn or with 2-3 shallow lobes and 2-5 awns (leaves on juvenile or 2d-flush growth may be deeply lobed with more awns), apex obtuse to blunt or rounded; surfaces abaxially glabrous except for minute or conspicuous axillary tufts of tomentum, veins rarely raised, adaxially glabrous with secondary veins somewhat impressed. |
blade narrowly lanceolate to usually oblong, mostly planar or slightly convex, 20-60(-90) × 10-20 mm, often rather leathery, base cuneate to rounded, margins coarsely 3-5-toothed on each side or shallowly lobed or entire, with teeth or lobes acute or obtuse, mucronate-tipped, secondary veins 4-6 on each side, usually branched, apex acute, rarely obtuse; surfaces abaxially densely stellate with minute appressed hairs, rarely glabrate and lustrous green, adaxially dark green, lustrous, glabrous or very sparsely stellate-puberulent. |
Acorns | biennial; cup saucer-shaped, 2.5-5.5 mm high × 10-18 mm wide, covering 1/4 nut or less, outer surface puberulent, inner surface sparsely to uniformly pubescent, scale tips tightly appressed, acute; nut broadly ovoid, 9.5-14 × 9.5-14.5 mm, often faintly striate, glabrate, scar diam. 6-11.5 mm. |
subsessile or on peduncle 2-3 mm; cup saucer-shaped to cup-shaped, 3-4 mm deep × 10 mm wide, margin thin, scales reddish brown, strongly, regularly tuberculate; nut light brown, ovoid to oblong or subcylindric, to 12 × 12 mm, glabrous. |
Cotyledons | distinct. |
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Terminal | buds reddish brown, ovoid, 3-6.5 mm, puberulent throughout, occasionally densely pubescent on apical 2/3. |
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Quercus nigra |
Quercus vaseyana |
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Phenology | Flowering spring. | Flowering spring. |
Habitat | Mesic alluvial and lowland sites, also barrens, dunes, hammocks, and low ridges to steep slopes | Dry limestone slopes, oak and mesquite woodlands, juniper woodlands, and canyons and ravines in otherwise dry, open grasslands, sometimes descending into margins of dry scrub |
Elevation | 0-450 m (0-1500 ft) | 300-600 m (1000-2000 ft) |
Distribution |
AL; AR; DE; FL; GA; KY; LA; MD; MO; MS; NC; NJ; OK; SC; TN; TX; VA
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TX; Mexico (Chihuahua, Coahuila, and Nuevo León) |
Discussion | Typically on mesic alluvial and lowland sites, Quercus nigra also occurs on a wide variety of soil types and in a diversity of habitats. Trees with 3-lobed leaves with attenuate bases have been recognized as Quercus nigra var. tridentifera Sargent. Quercus nigra reportedly hybridizes with Q. falcata (= Q. ×garlandensis E. J. Palmer), Q. incana, Q. laevis (= Q. ×walteriana Ashe), Q. marilandica (= Q. ×sterilis Trelease), Q. phellos (= Q. ×capesii W. Wolf), Q. shumardii (= Q. ×neopalmeri Sudworth), and Q. velutina (Q. ×demarei Ashe). In addition, D. M. Hunt (1989) cited evidence of hybridization also with Q. arkansana, Q. georgiana, Q. hemisphaerica, Q. laurifolia, Q. myrtifolia, Q. palustris, Q. rubra, and Q. texana. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Apparent hybridization between Quercus vaseyana and Q. pungens is discussed under the latter species. (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. nana, Q. nigra var. tridentifera, Q. uliginosa | Q. pungens var. vaseyana, Q. undulata var. vaseyana |
Name authority | Linnaeus: Sp. Pl. 2: 995. (1753) | Buckley: Bull. Torrey Bot. Club 10: 91. (1883) |
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