Quercus austrina

Small

Fl. S.E. U.S., 353. 1903.

Common names: Bastard white oak
EndemicIllustrated
Synonyms: Quercus durandii var. austrina (Small) E. J. Palmer
Treatment appears in FNA Volume 3.

Trees, deciduous, to 20 (-25) m. Bark pale gray, scaly, eventually divided into broad ridges. Twigs dark-brown to somewhat reddish, 2-2.5 mm diam., often with prominent, corky, white lenticels. Buds dark reddish-brown, ovoid, distally acute, 3-5 × 2-2.5 mm, puberulent. Leaves: petiole 3-5 mm. Leaf-blade green or grayish green, narrowly obovate or elliptic, (40-) 70-100 (-200) × (13-) 30-50 (-115) mm, base cuneate or attenuate, margins sinuately and irregularly shallowly lobed, lobes rounded, sometimes obtuse, secondary-veins 4-6 (-8) on each side, apex narrowly or broadly rounded; surfaces abaxially loosely covered with semierect stellate hairs to 0.5 mm diam., glabrous at maturity, often with a few hairs remaining along veins near midrib, adaxially glabrous, glossy. Acorns subsessile or on stout axillary peduncle to 15 mm; cup hemispheric or deeply goblet or cupshaped, 9-10 mm deep × 10-13 mm wide, enclosing 1/3-1/2 nut, scales loosely appressed, gray, narrowly ovate, sometimes thickened near base, not tuberculate, canescent; nut ovoid or elliptic, 17 × 12 mm. Cotyledons distinct.


Phenology: Flowering spring.
Habitat: River bottoms, wet forests, flatwoods
Elevation: 0-200 m

Distribution

V3 659-distribution-map.gif

Ala., Fla., Ga., Miss., N.C., S.C.

Discussion

Quercus austrina is probably the most misunderstood oak of the southeastern United States. Although the species is fairly widespread, it is apparently abundant only in local areas and is poorly represented in herbaria. This may be partly because Q. austrina is often misidentified as Q. sinuata, which it superficially resembles, or as Q. nigra, a red oak with similarly shaped leaves. It is easily distinguished from Q. sinuata by its larger, more acute buds; darker twigs; deeper, turbinate acorn cups; and absence of minute, appressed, stellate hairs on the abaxial leaf surface. Instead, Q. austrina has a tomentum of soft erect hairs on young leaves, and glabrate mature leaves.

Selected References

None.

Lower Taxa

None.
... more about "Quercus austrina"
on stout axillary peduncle +  and subsessile +
Kevin C. Nixon +
0 cm0 mm <br />0 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
divided +
attenuate;cuneate +
dark reddish-brown +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
puberulent +
Acute (?) +  and Ovoid (?) +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
2-6-lobed +
pistillate +, capitate +  and spicate +
Bastard white oak +
starchy +  and fleshy +
cup-shaped +, deeply +  and hemispheric +
×10-13 +, 9mm +  and 10mm +
multibracteate +, spiny +  and scaly +
Ala. +, Fla. +, Ga. +, Miss. +, N.C. +  and S.C. +
0-200 m +
pistillate +  and staminate +
biennial +, annual +  and maturation +
1-seeded +  and winged +
in groups +  and enclosed +
River bottoms, wet forests, flatwoods +
pistillate +, spicate +  and staminate +
tomentulose +  and glabrate +
10 cm100 mm <br />0.1 m <br /> (20 cm200 mm <br />0.2 m <br />) +
5 cm50 mm <br />0.05 m <br /> (11.5 cm115 mm <br />0.115 m <br />) +
grayish green +  and green +
7 cm70 mm <br />0.07 m <br /> (10 cm100 mm <br />0.1 m <br />) +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
arranged +  and alternate +
obtuse +  and rounded +
entire +, dentate +  and serrate +
17 cm170 mm <br />0.17 m <br /> (?) +
1/3 +  and 1/2 +
elliptic +  and ovoid +
12 cm120 mm <br />0.12 m <br /> (?) +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Flowering spring. +
Fl. S.E. U.S., +
connate +  and distinct +
few-to-many +
not tuberculate +
reduced +
anastomosing +, branching +  and unbranched +
Endemic +  and Illustrated +
inconspicuous +
distinct +
subulate +  and dilated +
enlarged +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
Quercus durandii var. austrina +
Quercus austrina +
Quercus sect. Quercus +
species +
spheric +  and ovoid terete or angled +
bristle-tipped +
reddish +  and dark-brown to somewhat +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +