FNA: Quercus texana vs. Quercus mohriana

	Quercus texana	Quercus mohriana
	Nuttall's oak, Texas red oak	Mohr oak, Mohr's oak, Mohr's shinoak
Habit	Trees, deciduous, to 25 m. Bark dark brown with flat ridges divided by shallow fissures.	Shrubs or trees, evergreen or deciduous, shrubs erect, rhizomatous, trees small, 0.5-3 m. Bark pale, rough and deeply furrowed.
Twigs	red-brown to gray, 1.5-3(-3.5) mm diam., glabrous.	yellowish or whitish, 1-2 mm diam., felty-tomentose.
Buds		dark red-brown, round-ovoid, 2 mm, glabrous, occasionally puberulent on outer scales, not subtended by persistent, hairy, subulate stipules.
Leaves	blade ovate to elliptic or obovate, 75-200 × 55-130 mm, base cuneate to almost truncate, often inequilateral, margins with 6-11 lobes and 9-24 awns, lobes oblong to distally expanded, rarely falcate, apex acute; surfaces abaxially glabrous except for conspicuous axillary tufts of tomentum, veins raised, adaxially planar, glabrous.	blade usually strongly bicolored, oblong or elliptic, (15-)30-50(-80) × (10-)20-30(-35) mm, leathery, base rounded, rarely cuneate or cordulate, margins entire or toothed or denticulate, undulate or flat, secondary veins 8-9 on each side, apex rounded or acute; surfaces abaxially densely gray- or white-tomentose with semi-erect curly, stellate hairs, secondary veins rather prominently raised, adaxially dark or dull green, lustrous or somewhat glaucous, with minute, scattered, semi-erect or appressed-stellate, (4-)6 or many rayed hairs, not felty to touch, secondary veins slightly raised or prominent within depressions.
Acorns	biennial; cup thin (scale bases visible on inner surface), deeply goblet-shaped with pronounced constriction at base, 10-16 mm high × 15-22 mm wide, covering 1/3-1/2 nut, outer surface glabrous to sparsely puberulent, inner surface sparsely to uniformly pubescent, scale tips appressed, acute; nut broadly ovoid to broadly ellipsoid, 15-26 × 13-18 mm, glabrous or sparsely puberulent, scar diam. 8-13 mm, scar often orangish.	solitary or paired, subsessile or peduncle sometimes 10-15 mm, tomentose like twigs; cup shallowly to very deeply cup-shaped, 5-12 mm deep × 8-18 mm wide, enclosing 1/2 nut, base rounded or flat, margin thin, scales triangular-ovate to oblong, proximal scales coarsely tuberculate and canescent-tomentose, distal ones usually elongate and narrowed, tips appressed, reddish, thin, nearly glabrous; nut light brown, ellipsoid to ovoid, 8-15 × 5-12 mm.
Cotyledons		connate.
Terminal	buds gray to gray-brown, ovoid, 3-7 mm, glabrous or with scales somewhat ciliate at apex.

	Quercus texana	Quercus mohriana
Phenology	Flowering spring.	Flowering spring.
Habitat	Flood plains and bottomlands	Limestone hills and slopes, calcareous substrates
Elevation	0-200 m (0-700 ft)	600-2500 m (2000-8200 ft)
Distribution	AL; AR; IL; KY; LA; MO; MS; TN; TX [WildflowerSearch map] [BONAP county map]	NM; OK; TX; Mexico (Coahuila) [WildflowerSearch map] [BONAP county map]
Discussion	For many years the name Quercus texana was erroneously used for Q. buckleyi (L. J. Dorr and K. C. Nixon 1985). A few authors have also used the name for Q. gravesii. Quercus nuttallii E. J. Palmer var. cachensis E. J. Palmer was described as a small-fruited form (nuts 16-18 × 12-16 mm) from specimens collected in east-central Arkansas (E. J. Palmer 1937). Noting the similarity between Q. nuttallii var. cachensis and Q. palustris, Palmer discounted the possibility of the former being of hybrid origin because (1) he had not observed Q. palustris in the type locality, and (2) the leaves and buds of the former were essentially the same as in Q. nuttallii var. nuttallii. C. H. Muller (1942), on the other hand, argued that Quercus nuttallii was nothing more than a form [forma nuttallii (E. J. Palmer) C. H. Muller] of Q. palustris. This is a puzzling conclusion because it was based largely on the premise that Q. nuttallii occurred "...with the parent species throughout a large part of the latter's southern range (Mississippi to eastern Texas and southeastern Missouri)." The range of Q. palustris does not extend into Mississippi or eastern Texas, although its range does overlap that of Q. texana in eastern Arkansas and southeastern Missouri. E. J. Palmer (1948) and D. M. Hunt (1989) have suggested hybridization with Q. shumardii and Q. nigra, respectively. See L. J. Dorr and K. C. Nixon (1985) for an explanation of the nomenclatural confusion regarding this taxon. (Discussion copyrighted by Flora of North America; reprinted with permission.)	Putative hybrids between Quercus mohriana Buckley and Q. grisea Liebmann are problematic and highly polymorphic. They are restricted to zones of contact between limestone, the preferred habitat of Q. mohriana, and igneous substrates, the preferred habitat of Q. grisea, or sometimes on dolomite, in western Texas. (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	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. robur, Q. robusta, Q. rubra, Q. rugosa, Q. sadleriana, Q. shumardii, Q. similis, Q. sinuata, Q. stellata, Q. tardifolia, 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. 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
Synonyms	Q. nuttallii, Q. rubra var. texana, Q. shumardii var. texana
Name authority	Buckley: Proc. Acad. Nat. Sci. Philadelphia 12: 444. (1860)	Buckley: in Rydberg, Bull. New York Bot. Gard. 2: 219. (1901)
Web links	Local Web sites: IL Wildflowers, LA Plants, MO Plants WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Quercus mohriana

Nuttall's oak, Texas red oak

Mohr oak, Mohr's oak, Mohr's shinoak

Habit

Trees, deciduous, to 25 m. Bark dark brown with flat ridges divided by shallow fissures.

Shrubs or trees, evergreen or deciduous, shrubs erect, rhizomatous, trees small, 0.5-3 m. Bark pale, rough and deeply furrowed.

Twigs

red-brown to gray, 1.5-3(-3.5) mm diam., glabrous.

yellowish or whitish, 1-2 mm diam., felty-tomentose.

Buds

dark red-brown, round-ovoid, 2 mm, glabrous, occasionally puberulent on outer scales, not subtended by persistent, hairy, subulate stipules.

Leaves

blade ovate to elliptic or obovate, 75-200 × 55-130 mm, base cuneate to almost truncate, often inequilateral, margins with 6-11 lobes and 9-24 awns, lobes oblong to distally expanded, rarely falcate, apex acute;

surfaces abaxially glabrous except for conspicuous axillary tufts of tomentum, veins raised, adaxially planar, glabrous.

blade usually strongly bicolored, oblong or elliptic, (15-)30-50(-80) × (10-)20-30(-35) mm, leathery, base rounded, rarely cuneate or cordulate, margins entire or toothed or denticulate, undulate or flat, secondary veins 8-9 on each side, apex rounded or acute;

surfaces abaxially densely gray- or white-tomentose with semi-erect curly, stellate hairs, secondary veins rather prominently raised, adaxially dark or dull green, lustrous or somewhat glaucous, with minute, scattered, semi-erect or appressed-stellate, (4-)6 or many rayed hairs, not felty to touch, secondary veins slightly raised or prominent within depressions.

Acorns

biennial;

cup thin (scale bases visible on inner surface), deeply goblet-shaped with pronounced constriction at base, 10-16 mm high × 15-22 mm wide, covering 1/3-1/2 nut, outer surface glabrous to sparsely puberulent, inner surface sparsely to uniformly pubescent, scale tips appressed, acute;

nut broadly ovoid to broadly ellipsoid, 15-26 × 13-18 mm, glabrous or sparsely puberulent, scar diam. 8-13 mm, scar often orangish.

solitary or paired, subsessile or peduncle sometimes 10-15 mm, tomentose like twigs;

cup shallowly to very deeply cup-shaped, 5-12 mm deep × 8-18 mm wide, enclosing 1/2 nut, base rounded or flat, margin thin, scales triangular-ovate to oblong, proximal scales coarsely tuberculate and canescent-tomentose, distal ones usually elongate and narrowed, tips appressed, reddish, thin, nearly glabrous;

nut light brown, ellipsoid to ovoid, 8-15 × 5-12 mm.

Cotyledons

connate.

Terminal

buds gray to gray-brown, ovoid, 3-7 mm, glabrous or with scales somewhat ciliate at apex.

Quercus texana

Quercus mohriana

Phenology

Flowering spring.

Habitat

Flood plains and bottomlands

Limestone hills and slopes, calcareous substrates

Elevation

0-200 m (0-700 ft)

600-2500 m (2000-8200 ft)

Distribution

AL; AR; IL; KY; LA; MO; MS; TN; TX

[WildflowerSearch map]

[BONAP county map]

NM; OK; TX; Mexico (Coahuila)

[WildflowerSearch map]

[BONAP county map]

Discussion

For many years the name Quercus texana was erroneously used for Q. buckleyi (L. J. Dorr and K. C. Nixon 1985). A few authors have also used the name for Q. gravesii.

Quercus nuttallii E. J. Palmer var. cachensis E. J. Palmer was described as a small-fruited form (nuts 16-18 × 12-16 mm) from specimens collected in east-central Arkansas (E. J. Palmer 1937). Noting the similarity between Q. nuttallii var. cachensis and Q. palustris, Palmer discounted the possibility of the former being of hybrid origin because (1) he had not observed Q. palustris in the type locality, and (2) the leaves and buds of the former were essentially the same as in Q. nuttallii var. nuttallii.

C. H. Muller (1942), on the other hand, argued that Quercus nuttallii was nothing more than a form [forma nuttallii (E. J. Palmer) C. H. Muller] of Q. palustris. This is a puzzling conclusion because it was based largely on the premise that Q. nuttallii occurred "...with the parent species throughout a large part of the latter's southern range (Mississippi to eastern Texas and southeastern Missouri)." The range of Q. palustris does not extend into Mississippi or eastern Texas, although its range does overlap that of Q. texana in eastern Arkansas and southeastern Missouri. E. J. Palmer (1948) and D. M. Hunt (1989) have suggested hybridization with Q. shumardii and Q. nigra, respectively. See L. J. Dorr and K. C. Nixon (1985) for an explanation of the nomenclatural confusion regarding this taxon.

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

Putative hybrids between Quercus mohriana Buckley and Q. grisea Liebmann are problematic and highly polymorphic. They are restricted to zones of contact between limestone, the preferred habitat of Q. mohriana, and igneous substrates, the preferred habitat of Q. grisea, or sometimes on dolomite, in western Texas.

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

Source

FNA vol. 3.

Parent taxa

Fagaceae > Quercus > sect. Lobatae

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. 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. robur, Q. robusta, Q. rubra, Q. rugosa, Q. sadleriana, Q. shumardii, Q. similis, Q. sinuata, Q. stellata, Q. tardifolia, 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. 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

Synonyms

Q. nuttallii, Q. rubra var. texana, Q. shumardii var. texana

Name authority

Buckley: Proc. Acad. Nat. Sci. Philadelphia 12: 444. (1860)

Buckley: in Rydberg, Bull. New York Bot. Gard. 2: 219. (1901)

Web links

Local Web sites: IL Wildflowers, LA Plants, MO Plants
WildflowerSearch
iNaturalist (observations)
USDA Plants Database
LBJ Wildflower Center
SEINet
Plants of the World Online
Encyclopedia of Life
Wikipedia
Google Image Search

Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).

Choose a data source: Flora of North America

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Flora of North America species comparison

Quercus texana

Quercus mohriana

Quercus texana

Quercus mohriana