Quercus fusiformis |
Quercus garryana |
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escarpment live oak, live oak, plateau oak, Texas live oak |
Garry oak, Oregon oak, Oregon white oak |
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Habit | Trees, sometimes shrubs, subevergreen, trees to 25 m, shrubs often forming large clonal stands. | Trees or shrubs, deciduous, trees to 15(-20) m, with solitary trunks, shrubs to 0.1-3 m, multitrunked. | ||||||||
Bark | dark brown or black, scaly. |
light gray or almost white, scaly. |
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Twigs | light gray, 1.5-3 mm diam., tomentulose, tomentulum often persistent in age. |
brown, red, or yellowish, 2-4 mm diam., densely puberulent with spreading hairs or glabrate. |
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Buds | reddish or dark brown, subglobose or ovate, 1.5-3 mm; scale margins glabrous or puberulent. |
brown or yellowish, ovoid or fusiform and apex acute, 2-12 mm, glandular-puberulent or densely pubescent. |
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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, elliptic or subrotund, moderately to deeply lobed, 25-120(-140) × 15-85 mm, base rounded-attenuate or cuneate, rarely subcordate, often unequal, margins with sinuses usually reaching more than 1/2 distance to midrib, lobes oblong or spatulate, obtuse, rounded or blunt, larger lobes usually with 2-3 sublobes or teeth, veins often ending in retuse teeth, secondary veins yellowish, 4-7 on each side, the more distal veins often branching within distal lobes, apex broadly rounded; surfaces abaxially light green or waxy yellowish, often felty to touch, densely to sparsely covered with semi-erect or erect, simple and (2-)4-8-rayed, fasciculate hairs 0.1-1 mm, secondary veins raised, adaxially bright or dark green, glossy or somewhat scurfy because of sparse stellate hairs. |
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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, subsessile, rarely on peduncle to 10(-20) mm; cup saucer-shaped, cup-shaped, or hemispheric, 4-10 mm deep × 12-22 mm wide; scales yellowish or reddish brown, often long-acute near rim of cup, moderately or scarcely tuberculate, canescent or tomentulose; nut light brown, oblong to globose, (12-)25-30(-40) × (10-)14-20(-22) mm, apex blunt or rounded, glabrous or often persistently puberulent. |
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Cotyledons | connate. |
distinct. |
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2n | = 24. |
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Quercus fusiformis |
Quercus garryana |
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Phenology | 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 | |||||||||
Elevation | 0-1200 m (0-3900 ft) | |||||||||
Distribution |
OK; TX; Mexico (Coahuila, Nuevo León, and Tamaulipas)
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CA; OR; WA; BC
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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.) |
Varieties 3 (3 in the flora). Quercus garryana (no varieties specified) was used medicinally by Native Americans to treat tuberculosis and as a drink and a rub for mothers before childbirth (D. E. Moerman 1986). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 3. | FNA vol. 3. | ||||||||
Parent taxa | Fagaceae > Quercus > sect. Quercus | Fagaceae > Quercus > sect. Quercus | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | Q. virginiana var. fusiformis | Q. douglasii var. neaei, Q. garryana var. jacobi, Q. jacobi, Q. lobata var. breweri, Q. neaei | ||||||||
Name authority | Small: Bull. Torrey Bot. Club 28: 357. (1901) | Douglas ex Hooker: Fl. Bor.-Amer. 2: 159. (1840) | ||||||||
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