FNA: Quercus arizonica vs. Quercus minima

	Quercus arizonica	Quercus minima
	Arizona oak, Arizona white oak	dwarf live oak, minimal oak
Habit	Trees, evergreen or subevergreen, small to moderate-sized trees, rarely to 18 m. Bark scaly.	Shrubs, subevergreen or evergreen, low, rhizomatous, forming clonal patches of straight, often unbranched stems 0.2-0.7(-2) m. Bark light gray or brown, smooth.
Twigs	yellowish, 1.5-2.5 mm diam., persistently felty-tomentose, eventually dingy gray.	light gray, 1.5-3 mm diam., glabrous or very finely tomentulose and glabrate in 2d year.
Buds	dull russet-brown, ovoid, distally subacute or rounded, 3 mm, sparsely pubescent or glabrate.	dark gray-brown, globose, 0.5-1(-1.5) mm; scale margins glabrous or puberulent.
Leaves	blade elliptic or oblong to narrowly obovate or oblanceolate, planar or moderately convex, to (30-)40-80(-90) × 15-30 mm, thick and leathery, usually stiff, base cordate or rounded and weakly cordate, margins entire or coarsely toothed especially near apex, cartilaginously revolute, teeth mucronate-tipped, obscure or prominent, secondary veins ca. 7-11 on each side, branching, passing into teeth when present, apex acute to usually obtuse or broadly rounded; surfaces abaxially dull, sparsely pubescent or subtomentose with curly branched hairs, reticulate from prominent, raised secondary veins, usually glaucous where exposed, adaxially dark or bluish green, moderately lustrous, sparsely and minutely stellate-pubescent, secondary veins slightly raised or prominent within depressions or impressed.	blade obovate to oblanceolate, sometimes orbiculate or lance-ovate, often asymmetric, 40-120 × 20-50 mm proximally on shoots, narrowly elliptic, 20-60 × 5-20 mm distally on shoots, base cuneate, rarely truncate or cordate, margins minutely revolute or flat, coarsely and irregularly 1-5 toothed on each side (proximal leaves of shoots) or entire (distal leaves on shoots), teeth mucronate (rarely spinose in suckers or juveniles), secondary veins obscure, 4-10(-12) on each side, usually 4-6 in proximal leaves, 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.
Acorns	solitary or paired, subsessile, occasionally on peduncle to 15 mm; cup hemispheric or cup-shaped, 5-10(-15) mm deep × 10-15 mm wide, enclosing ca. 1/2 nut, base rounded, margin rather coarse, scales cream to brown, broadly ovate, evenly and strongly tuberculate, tomentose, tips closely appressed; nut light brown, ovoid or oblong, 8-12 mm, nearly glabrous.	1-3, on peduncle 3-30 mm; cup hemispheric or deeply goblet-shaped, (8-)10-15 mm deep × 6-15 mm wide, base often constricted, scales whitish or grayish, thickened basally, keeled, acute-attenuate, tomentulose, tips reddish, glabrous or puberulent; nut dark brown, narrowly ovoid or subcylindric, 13-22(-25) × 8-15 mm, glabrous.
Cotyledons	connate.	connate.

	Quercus arizonica	Quercus minima
Phenology	Flowering spring.	Flowering spring.
Habitat	Oak and pinyon woodlands, margins of chaparral, arroyos	Coastal plain, open evergreen woodlands and scrublands on deep sandy soils, often as understory with pines
Elevation	1300-2500(-3000) m (4300-8200(-9800) ft)	0-200 m (0-700 ft)
Distribution	AZ; NM; TX; Mexico (Chihuahua, Coahuila, Durango, and Sonora) [WildflowerSearch map] [BONAP county map]	FL; GA; MS; NC; SC [WildflowerSearch map] [BONAP county map]
Discussion	Some of the specimens previously referred to Quercus endemica by C. H. Muller belong here instead. Putative hybrids between Quercus arizonica and Q. grisea (= Q. ×organensis Trelease) are problematic in local areas of contact from southeastern Arizona to western Texas. These intermediates tend to have narrower leaves than Q. arizonica, with moderately reticulate patterns of venation, and more densely hairy leaves. Quercus arizonica and Q. grisea are amply distinct elsewhere, including large areas in northern Mexico, and they appear to be more closely related to other species than to one another (e.g., Q. arizonica with Q. oblongifolia and Q. laeta Liebmann, and Q. grisea with Q. mohriana and Q. microphylla Née). Thus, Q. arizonica and Q. grisea are best treated as distinct species that hybridize, and not as conspecific populations. (Discussion copyrighted by Flora of North America; reprinted with permission.)	Quercus minima is one of the most distinctive oaks of southeastern United States in morphology, habit, and habitat. It is one of our most strongly rhizomatous species, and it flowers and fruits as early as three years from seed, on vertical stems as small as 0.2-0.3 m. Other related live oaks of Quercus series Virentes (see C. H. Muller 1961) can produce rhizomatous clonal patches as well, but these typically do not bear fruit, are usually associated with large shrub or tree forms, and probably represent response to fire and/or drought conditions. Because of the juvenile phases in other live oaks that may resemble Q. minima, it is necessary to evaluate form and reproductive capacity within populations to identify those species accurately. Putative hybrid swarms between Quercus minima and Q. chapmanii occur along the eastern side of Florida. These are rhizomatous shrubs with leaves somewhat intermediate between the two parents. The leaves are broadly rounded apically and basally, and sparsely stellate abaxially. The fruit resembles that of Q. minima. Material of such affinity, but with larger nuts (to 25 mm), was the basis for Q. rolfsii Small. More data on variation in cotyledon fusion in the putative hybrid swarms would be useful because Q. minima has connate cotyledons and those of Q. chapmanii are distinct. Quercus minima has been reported from coastal Texas (C. H. Muller 1970), but that material is probably best referred to Q. fusiformis and possible introgressants from Q. virginiana and Q. oleoides. Typical Q. minima is not known from west of Mississippi. The Texas populations that have been referred here lack leaf dimorphism, leaf shape, and venation of Q. minima. Instead, they seem to be part of an extremely variable complex of erect shrubs, rhizomatous shrubs, and trees that have leaves varying in form between those of Q. fusiformis and Q. oleoides (e.g., the type of Q. oleoides var. quaterna C. H. Muller). If Q. minima occurred on the Texas coast in the past, its presence there has been so diluted by introgression that it is not now recognizable by the very distinctive and reliable characteristics that are used to identify it. (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 3.	FNA vol. 3.
Parent taxa	Fagaceae > Quercus > sect. Quercus	Fagaceae > Quercus > sect. Quercus
Sibling taxa	Q. acerifolia, Q. agrifolia, Q. ajoensis, Q. alba, 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. texana, 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. 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. texana, Q. tomentella, Q. toumeyi, Q. turbinella, Q. vacciniifolia, Q. vaseyana, Q. velutina, Q. viminea, Q. virginiana, Q. wislizenii
Synonyms	Q. sacame	Q. virginiana var. minima, Q. virens var. dentata, Q. virginiana var. dentata
Name authority	Sargent: Gard. & Forest 8: 92. (1895)	(Sargent) Small: Bull. Torrey Bot. Club 24: 438. (1897)
Web links	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 minima

Arizona oak, Arizona white oak

dwarf live oak, minimal oak

Habit

Trees, evergreen or subevergreen, small to moderate-sized trees, rarely to 18 m. Bark scaly.

Shrubs, subevergreen or evergreen, low, rhizomatous, forming clonal patches of straight, often unbranched stems 0.2-0.7(-2) m. Bark light gray or brown, smooth.

Twigs

yellowish, 1.5-2.5 mm diam., persistently felty-tomentose, eventually dingy gray.

light gray, 1.5-3 mm diam., glabrous or very finely tomentulose and glabrate in 2d year.

Buds

dull russet-brown, ovoid, distally subacute or rounded, 3 mm, sparsely pubescent or glabrate.

dark gray-brown, globose, 0.5-1(-1.5) mm;

scale margins glabrous or puberulent.

Leaves

blade elliptic or oblong to narrowly obovate or oblanceolate, planar or moderately convex, to (30-)40-80(-90) × 15-30 mm, thick and leathery, usually stiff, base cordate or rounded and weakly cordate, margins entire or coarsely toothed especially near apex, cartilaginously revolute, teeth mucronate-tipped, obscure or prominent, secondary veins ca. 7-11 on each side, branching, passing into teeth when present, apex acute to usually obtuse or broadly rounded;

surfaces abaxially dull, sparsely pubescent or subtomentose with curly branched hairs, reticulate from prominent, raised secondary veins, usually glaucous where exposed, adaxially dark or bluish green, moderately lustrous, sparsely and minutely stellate-pubescent, secondary veins slightly raised or prominent within depressions or impressed.

blade obovate to oblanceolate, sometimes orbiculate or lance-ovate, often asymmetric, 40-120 × 20-50 mm proximally on shoots, narrowly elliptic, 20-60 × 5-20 mm distally on shoots, base cuneate, rarely truncate or cordate, margins minutely revolute or flat, coarsely and irregularly 1-5 toothed on each side (proximal leaves of shoots) or entire (distal leaves on shoots), teeth mucronate (rarely spinose in suckers or juveniles), secondary veins obscure, 4-10(-12) on each side, usually 4-6 in proximal leaves, 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.

Acorns

solitary or paired, subsessile, occasionally on peduncle to 15 mm;

cup hemispheric or cup-shaped, 5-10(-15) mm deep × 10-15 mm wide, enclosing ca. 1/2 nut, base rounded, margin rather coarse, scales cream to brown, broadly ovate, evenly and strongly tuberculate, tomentose, tips closely appressed;

nut light brown, ovoid or oblong, 8-12 mm, nearly glabrous.

1-3, on peduncle 3-30 mm;

cup hemispheric or deeply goblet-shaped, (8-)10-15 mm deep × 6-15 mm wide, base often constricted, scales whitish or grayish, thickened basally, keeled, acute-attenuate, tomentulose, tips reddish, glabrous or puberulent;

nut dark brown, narrowly ovoid or subcylindric, 13-22(-25) × 8-15 mm, glabrous.

Cotyledons

connate.

Quercus arizonica

Quercus minima

Phenology

Flowering spring.

Habitat

Oak and pinyon woodlands, margins of chaparral, arroyos

Coastal plain, open evergreen woodlands and scrublands on deep sandy soils, often as understory with pines

Elevation

1300-2500(-3000) m (4300-8200(-9800) ft)

0-200 m (0-700 ft)

Distribution

AZ; NM; TX; Mexico (Chihuahua, Coahuila, Durango, and Sonora)

[WildflowerSearch map]

[BONAP county map]

FL; GA; MS; NC; SC

[WildflowerSearch map]

[BONAP county map]

Discussion

Some of the specimens previously referred to Quercus endemica by C. H. Muller belong here instead.

Putative hybrids between Quercus arizonica and Q. grisea (= Q. ×organensis Trelease) are problematic in local areas of contact from southeastern Arizona to western Texas. These intermediates tend to have narrower leaves than Q. arizonica, with moderately reticulate patterns of venation, and more densely hairy leaves. Quercus arizonica and Q. grisea are amply distinct elsewhere, including large areas in northern Mexico, and they appear to be more closely related to other species than to one another (e.g., Q. arizonica with Q. oblongifolia and Q. laeta Liebmann, and Q. grisea with Q. mohriana and Q. microphylla Née). Thus, Q. arizonica and Q. grisea are best treated as distinct species that hybridize, and not as conspecific populations.

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

Quercus minima is one of the most distinctive oaks of southeastern United States in morphology, habit, and habitat. It is one of our most strongly rhizomatous species, and it flowers and fruits as early as three years from seed, on vertical stems as small as 0.2-0.3 m. Other related live oaks of Quercus series Virentes (see C. H. Muller 1961) can produce rhizomatous clonal patches as well, but these typically do not bear fruit, are usually associated with large shrub or tree forms, and probably represent response to fire and/or drought conditions. Because of the juvenile phases in other live oaks that may resemble Q. minima, it is necessary to evaluate form and reproductive capacity within populations to identify those species accurately.

Putative hybrid swarms between Quercus minima and Q. chapmanii occur along the eastern side of Florida. These are rhizomatous shrubs with leaves somewhat intermediate between the two parents. The leaves are broadly rounded apically and basally, and sparsely stellate abaxially. The fruit resembles that of Q. minima. Material of such affinity, but with larger nuts (to 25 mm), was the basis for Q. rolfsii Small. More data on variation in cotyledon fusion in the putative hybrid swarms would be useful because Q. minima has connate cotyledons and those of Q. chapmanii are distinct.

Quercus minima has been reported from coastal Texas (C. H. Muller 1970), but that material is probably best referred to Q. fusiformis and possible introgressants from Q. virginiana and Q. oleoides. Typical Q. minima is not known from west of Mississippi. The Texas populations that have been referred here lack leaf dimorphism, leaf shape, and venation of Q. minima. Instead, they seem to be part of an extremely variable complex of erect shrubs, rhizomatous shrubs, and trees that have leaves varying in form between those of Q. fusiformis and Q. oleoides (e.g., the type of Q. oleoides var. quaterna C. H. Muller). If Q. minima occurred on the Texas coast in the past, its presence there has been so diluted by introgression that it is not now recognizable by the very distinctive and reliable characteristics that are used to identify it.

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

Source

FNA vol. 3.

Parent taxa

Fagaceae > Quercus > sect. Quercus

Sibling taxa

Q. acerifolia, Q. agrifolia, Q. ajoensis, Q. alba, 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. texana, 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. 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. texana, Q. tomentella, Q. toumeyi, Q. turbinella, Q. vacciniifolia, Q. vaseyana, Q. velutina, Q. viminea, Q. virginiana, Q. wislizenii

Synonyms

Q. sacame

Q. virginiana var. minima, Q. virens var. dentata, Q. virginiana var. dentata

Name authority

Sargent: Gard. & Forest 8: 92. (1895)

(Sargent) Small: Bull. Torrey Bot. Club 24: 438. (1897)

Web links

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

The species comparison tool is brought to you by:

Flora of North America species comparison

Quercus arizonica

Quercus minima

Quercus arizonica

Quercus minima