Quercus pumila |
Quercus geminata |
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runner oak, running oak |
sand live oak |
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Habit | Shrubs, deciduous or tardily deciduous, to 1 m. Bark gray to dark brown. | Trees, sometimes shrubs, subevergreen, trees to 25 m, shrubs sometimes rhizomatous (if spreading rhizomatously, without numerous straight, short, erect stems emerging from gound, or if so, mixed with other larger branches, infertile, and without dimorphic or asymmetric leaf form). |
Bark | dark brown or black, scaly. |
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Twigs | gray-brown to reddish brown, 1-2 mm diam., sparsely to uniformly pubescent. |
yellowish, becoming light gray, 1.5-3 mm diam., tomentulose, glabrate in 2d year. |
Buds | reddish or dark brown, globose or ovoid, 1-2.5(-3) mm; scale margins glabrous or puberulent. |
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Leaves | blade oblong to narrowly obovate, 25-100 × 10-33 mm, base acute to rounded, margins entire, revolute, with 1 apical awn, apex acute or obtuse to rounded; surfaces abaxially uniformly gray-brown pubescent, rarely glabrate, adaxially somewhat convex, rugose, glabrous or with scattered hairs along midrib. |
blade narrowly lanceolate or elliptic, rarely orbiculate, convex-cupped, (10-)35-60(-120) × (7-)10-30(-45) mm, base narrowly cuneate, rarely truncate or rounded, margins strongly revolute, entire, secondary veins 8-10(-12) on each side, apex acute, sometimes obtuse; surfaces abaxially whitish or glaucous, densely covered with minute, appressed, fused-stellate hairs (visible under magnification), and with additional scattered, erect, felty or spreading hairs (sometimes deciduous), or light green and glabrate in shade leaves, adaxially dark or light green, glossy, glabrous or with minute, scattered, stellate hairs, secondary veins moderately to deeply impressed. |
Acorns | annual; cup deeply saucer-shaped to turbinate, 5-12 mm high × 10-15 mm wide, covering 1/3-1/2(-2/3) nut, outer surface pubescent, inner surface densely pubescent, scales rarely involute, often tuberculate, tips tightly appressed, acute; nut globose to ovoid or broadly oblong, 9.5-15 × 9-12 mm, glabrate, scar diam. 5-8 mm. |
1-3, on peduncle 10-100 mm; cup hemispheric or deeply goblet-shaped, sometimes saucer-shaped, 8-15 mm deep × 5-15 mm wide, base often constricted, scales whitish or grayish, thickened basally, keeled, acute-attenuate, tomentulose, tips reddish, glabrous or puberulent; nut dark brown, ovoid, barrel-shaped, or acute, (13-)15-20(-25) × (8-)9-12(-15) mm, glabrous. |
Cotyledons | connate. |
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Terminal | buds brown to red-brown, ovoid, 2.5-4.5 mm, glabrous or with ciliate scale margins. |
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Quercus pumila |
Quercus geminata |
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Phenology | Flowering spring. | Flowering spring. |
Habitat | Dry sandy soils of savannahs, low ridges and oak-pine scrub, occasionally at margins of poorly drained sites | Coastal plain, open evergreen woodlands and scrublands on deep sandy soils, often with pines |
Elevation | 0-100 m (0-300 ft) | 0-200 m (0-700 ft) |
Distribution |
AL; FL; GA; MS; NC; SC
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AL; FL; GA; LA; MS; NC; SC
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Discussion | Although no hybrid combinations have been formally proposed, D. M. Hunt (1989) has reported evidence of hybridization with Quercus hemisphaerica, Q. incana, Q. myrtifolia, and Q. phellos. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Quercus geminata occurs in Cuba as putative hybrids. Although some recent authors prefer to treat Quercus geminata as a variety of Q. virginiana, the two species are easily separable and rarely intergrade through most of the broad range in which they are sympatric. Apparently this is primarily because of habitat separation, but additionally Q. geminata flowers much later than Q. virginiana in any given geographic area. At the northern extreme of the range of Q. geminata, apparent intermediates with Q. virginiana are more common, possibly because flowering times of the two species overlap to a greater extent because of slower warming in the spring. Scattered intermediates also occur where the two species are sympatric on sands in coastal Mississippi. (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. virginiana var. geminata | |
Name authority | Walter: Fl. Carol., 234. (1788) | Small: Bull. Torrey Bot. Club 24: 438. (1897) |
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