FNA: Quercus tomentella vs. Quercus wislizenii

	Quercus tomentella	Quercus wislizenii
	Channel Island oak, island live oak, island oak	interior live oak, Sierra live oak
Habit	Trees, to 20 m. Twigs branching at 45° angles, reddish brown, 3-4 mm diam., somewhat rigid, densely tomentose, persistent into 2d year.	Trees or shrubs, evergreen, to 22 m. Bark nearly black, deeply furrowed with broad scaly ridges.
Twigs		brown to red-brown, 1.5-3 mm diam., glabrous or sparsely pubescent.
Leaves	blade wavy or distinctly concave, oblong-lanceolate or elliptic, acuminate, (30-)70-10(-120) × 25-40 mm, leathery and brittle, base obtuse to cordate, secondary veins 8-10(-12) pairs, branching at 45-50° angles, strongly pinnate, raised abaxially, often sunken adaxially, margins often strongly revolute, with slightly thickened cell walls, entire or crenate to dentate with mucronate teeth, apex rounded or acute, mucronate; surfaces abaxially densely tomentose with whitish nonglandular hairs, midrib pilose, adaxially glossy dark green, sparsely pubescent.	blade circular to oblong, usually ovate, planar, 25-70 × 20-50 mm, base obtuse to cordate, margins entire or spinose with up to 16 awns, apex acute to rounded; surfaces abaxially and adaxially glabrous, veins little raised on either surface.
Acorns	solitary or rarely paired; cup shallowly cup-shaped, 4-8 mm deep × 15-30 mm wide, scales laterally connate, appressed, deeply imbedded in tomentum, with only thin, brown, elongated apices visible, tuberculate, densely whitish brown tomentose throughout; nut ovoid, 20-30 × 15-20 mm, apex rounded.	biennial; cup deeply and narrowly cup-shaped or U-shaped, 9-19 mm high × 7-18 mm wide, covering 1/3-1/2(-2/3) nut, outer surface glabrous to sparsely puberulent, inner surface glabrous or pubescent on innermost 1/3, occasionally uniformly pubescent, scales acute, tips loose; nut narrowly conic or ovoid to narrowly oblong, 21-44 × 8-14 mm, glabrous, scar diam. 2.5-7.5 mm.
Terminal	buds conic, 7-10 mm, scales brown with ciliate margins.	buds light chestnut brown to dark reddish brown, ovoid to conic, 3-9 mm, glabrous or with tuft of minute hairs at apex.
2n		= 24.

	Quercus tomentella	Quercus wislizenii
Phenology	Flowering in spring, occasionally in fall.	Flowering late spring.
Habitat	Lower portions of steep canyons and occasionally ridge tops	Valleys, slopes, and sand chaparral
Elevation	100-650 m (300-2100 ft)	300-1900 m (1000-6200 ft)
Distribution	CA; Mexico (Baja California and on Guadalupe Island) [WildflowerSearch map] [BONAP county map]	CA [WildflowerSearch map]
Discussion	The insular endemic Quercus tomentella is a relict as evidenced by its widespread representation in mainland late Tertiary fossil floras. Hybridization with Q. chrysolepis is apparent on the Channel Islands: Santa Catalina, Santa Cruz, and possibly San Clemente and Anacapa. Putative hybrids have been observed in narrow zones of contact on the islands of Santa Cruz and Santa Catalina. On those islands, taxonomically distinct individuals of Q. chrysolepis occur at the highest elevations, whereas Q. tomentella generally is found in moist canyons at lower elevations. Populations of Channel Island oak are in decline because of overgrazing and poor seedling recruitment. The greatest number of populations occur on Santa Rosa Island, and those are taxonomically and genetically noteworthy because Q. chrysolepis apparently is absent from the island. (Discussion copyrighted by Flora of North America; reprinted with permission.)	Shrubs with oval leaves 25-38 mm and margins entire or deeply lobed-dentate may be treated as Quercus wislizenii var. frutescens. J. M. Tucker (1993) treated Q. parvula as a distinct species, distinguished from Q. wislizenii by its larger leaves (30-90 versus 20-50 mm), by the dull, olive-green, abaxial leaf surface (versus shiny, yellow-green), and by nuts that are abruptly tapered proximal to the middle (versus gradually tapered). Tucker recognized two varieties of Quercus parvula: Q. parvula var. parvula is a shrub of 1-3 m and Q. parvula var. shrevei is a tree less than 17 m. S. K. Langer (1993) recognized a third variety, Q. parvula var. tamalpaisensis,based on several small populations on or near Mount Tamalpais, differentiated primarily by having larger leaves (50-160 × 20-60 mm) with attenuate-dentate margins. Quercus wislizenii reportedly hybridizes with Q. agrifolia and Q. kelloggii (W. B. Brophy and D. R. Parnell 1974). (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 3.	FNA vol. 3.
Parent taxa	Fagaceae > Quercus > sect. Protobalanus	Fagaceae > Quercus > sect. Lobatae
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. texana, 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. 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
Synonyms		Q. parvula, Q. parvula var. shrevei, Q. parvula var. tamalpaisensis, Q. wislizenii var. frutescens
Name authority	Engelmann: Trans. Acad. Sci. St. Louis, 3: 393. (1877)	A. de Candolle: in A. P. de Candolle and A. L. P. de Candolle, Prodr. 16(2): 67. (1864)
Web links	Local floras: CA Local Web sites: CalFlora, CalPhotos WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA Local Web sites: CalFlora, CalPhotos WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Quercus wislizenii

Channel Island oak, island live oak, island oak

interior live oak, Sierra live oak

Habit

Trees, to 20 m. Twigs branching at 45° angles, reddish brown, 3-4 mm diam., somewhat rigid, densely tomentose, persistent into 2d year.

Trees or shrubs, evergreen, to 22 m. Bark nearly black, deeply furrowed with broad scaly ridges.

Twigs

brown to red-brown, 1.5-3 mm diam., glabrous or sparsely pubescent.

Leaves

blade wavy or distinctly concave, oblong-lanceolate or elliptic, acuminate, (30-)70-10(-120) × 25-40 mm, leathery and brittle, base obtuse to cordate, secondary veins 8-10(-12) pairs, branching at 45-50° angles, strongly pinnate, raised abaxially, often sunken adaxially, margins often strongly revolute, with slightly thickened cell walls, entire or crenate to dentate with mucronate teeth, apex rounded or acute, mucronate;

surfaces abaxially densely tomentose with whitish nonglandular hairs, midrib pilose, adaxially glossy dark green, sparsely pubescent.

blade circular to oblong, usually ovate, planar, 25-70 × 20-50 mm, base obtuse to cordate, margins entire or spinose with up to 16 awns, apex acute to rounded;

surfaces abaxially and adaxially glabrous, veins little raised on either surface.

Acorns

solitary or rarely paired;

cup shallowly cup-shaped, 4-8 mm deep × 15-30 mm wide, scales laterally connate, appressed, deeply imbedded in tomentum, with only thin, brown, elongated apices visible, tuberculate, densely whitish brown tomentose throughout;

nut ovoid, 20-30 × 15-20 mm, apex rounded.

biennial;

cup deeply and narrowly cup-shaped or U-shaped, 9-19 mm high × 7-18 mm wide, covering 1/3-1/2(-2/3) nut, outer surface glabrous to sparsely puberulent, inner surface glabrous or pubescent on innermost 1/3, occasionally uniformly pubescent, scales acute, tips loose;

nut narrowly conic or ovoid to narrowly oblong, 21-44 × 8-14 mm, glabrous, scar diam. 2.5-7.5 mm.

Terminal

buds conic, 7-10 mm, scales brown with ciliate margins.

buds light chestnut brown to dark reddish brown, ovoid to conic, 3-9 mm, glabrous or with tuft of minute hairs at apex.

= 24.

Quercus tomentella

Quercus wislizenii

Phenology

Flowering in spring, occasionally in fall.

Flowering late spring.

Habitat

Lower portions of steep canyons and occasionally ridge tops

Valleys, slopes, and sand chaparral

Elevation

100-650 m (300-2100 ft)

300-1900 m (1000-6200 ft)

Distribution

CA; Mexico (Baja California and on Guadalupe Island)

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

Discussion

The insular endemic Quercus tomentella is a relict as evidenced by its widespread representation in mainland late Tertiary fossil floras. Hybridization with Q. chrysolepis is apparent on the Channel Islands: Santa Catalina, Santa Cruz, and possibly San Clemente and Anacapa. Putative hybrids have been observed in narrow zones of contact on the islands of Santa Cruz and Santa Catalina. On those islands, taxonomically distinct individuals of Q. chrysolepis occur at the highest elevations, whereas Q. tomentella generally is found in moist canyons at lower elevations. Populations of Channel Island oak are in decline because of overgrazing and poor seedling recruitment. The greatest number of populations occur on Santa Rosa Island, and those are taxonomically and genetically noteworthy because Q. chrysolepis apparently is absent from the island.

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

Shrubs with oval leaves 25-38 mm and margins entire or deeply lobed-dentate may be treated as Quercus wislizenii var. frutescens. J. M. Tucker (1993) treated Q. parvula as a distinct species, distinguished from Q. wislizenii by its larger leaves (30-90 versus 20-50 mm), by the dull, olive-green, abaxial leaf surface (versus shiny, yellow-green), and by nuts that are abruptly tapered proximal to the middle (versus gradually tapered).

Tucker recognized two varieties of Quercus parvula: Q. parvula var. parvula is a shrub of 1-3 m and Q. parvula var. shrevei is a tree less than 17 m. S. K. Langer (1993) recognized a third variety, Q. parvula var. tamalpaisensis,based on several small populations on or near Mount Tamalpais, differentiated primarily by having larger leaves (50-160 × 20-60 mm) with attenuate-dentate margins.

Quercus wislizenii reportedly hybridizes with Q. agrifolia and Q. kelloggii (W. B. Brophy and D. R. Parnell 1974).

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

Source

FNA vol. 3.

Parent taxa

Fagaceae > Quercus > sect. Protobalanus

Fagaceae > Quercus > sect. Lobatae

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. texana, 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. 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

Synonyms

Q. parvula, Q. parvula var. shrevei, Q. parvula var. tamalpaisensis, Q. wislizenii var. frutescens

Name authority

Engelmann: Trans. Acad. Sci. St. Louis, 3: 393. (1877)

A. de Candolle: in A. P. de Candolle and A. L. P. de Candolle, Prodr. 16(2): 67. (1864)

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

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Quercus tomentella

Quercus wislizenii

Quercus tomentella

Quercus wislizenii