A tree, usually 30°—40° high, with a short trunk 2°—3° in diameter, stout rigid rather drooping branches forming a round-topped symmetrical head, and slender rigid branchlets covered at first with close hoary tomentum, bright red, pubescent or tomentose in their first winter, ultimately glabrous and dark red-brown or black; sometimes 60°—70° high, with a trunk 4°—5° in diameter, with a head occasionally 100° across; or at high altitudes or on exposed mountain slopes a low shrub. Winter-buds ellipsoidal, acute, about ¼′ long, pale pubescent toward the apex, with thin closely imbricated light chestnut-brown ciliate scales. Bark 1′—2′ thick, dark brown or nearly black, deeply divided into large oblong thick plates separating into small thin closely appressed scales. Wood heavy, strong, brittle, close-grained, dark brown or almost black, with thick bright brown sapwood tinged with red. The sweet acorns are an important article of food for Mexicans and Indians, and are sold in the towns of southern Arizona and northern Mexico.
Distribution. Mountain ranges of western Texas, southern New Mexico, Arizona south of the Colorado plateau, and of northern Mexico; in Texas common in the cañons and on the southern slopes of the Limpio and Chisos mountains; the most abundant Oak of southern New Mexico and Arizona, forming a large part of the forests covering the mountain slopes and extending from the upper limits of the mesa nearly to the highest ridges; attaining its largest size and beauty in the moist soil of sheltered cañons.
28. [Quercus dumosa] Nutt. Scrub Oak.
Leaves oblong, rounded and acute at apex, broad and abruptly cuneate or rounded at base, usually about ¾′ long and ½′ wide, spinescent with a few minute teeth, or undulate and entire or coarsely spinescent, with an obscure midrib and primary veins, conspicuous reticulate veinlets, and stout petioles rarely ⅛′ long; or sometimes oblong to oblong-obovate and divided by deep sinuses into 5—9 oblong acute rounded or emarginate bristle-tipped lobes, the terminal lobe 3-lobed, rounded or acute, 2′—4′ long and 1′—1½′ wide, with primary veins running to the points of the lobes, obscure reticulate veinlets, and petioles sometimes 1′ long, thin when they unfold and clothed with scattered fascicled hairs, or rarely tomentose above and coated below and on the petioles with hoary tomentum, at maturity thick and firm, dark green and glabrous on the upper surface, paler and more or less pubescent on the lower surface; mostly deciduous during the winter. Flowers: staminate in pubescent aments; calyx divided into 4—7 ovate lanceolate hairy segments; pistillate sessile or stalked, in long many-flowered tomentose spikes, their involucral scales and calyx hoary-tomentose; stigmas red. Fruit sessile or short-stalked; nut ovoid, broad at base, broad and rounded or acute at apex, ½′—1′ long, ⅓′—⅔′ thick, inclosed for one half to two thirds its length in a deep cup-shaped or hemispheric cup light brown and pubescent within, covered by ovate pointed scales coated with pale or rufous tomentum, usually much thickened, united and tuberculate, those above with free acute tips forming a fringe to the rim of the cup, or frequently with basal scales but little thickened and furnished with long free tips; in var. Alvordiana Jeps., with a nut 1½′—1⅝′ long, ¼′—½′ thick, gradually narrowed and acute at apex, inclosed only at base in a shallow cup-shaped cup.
A tree, rarely 20° high, with a trunk 12′—18′ in diameter, small branches forming a round-topped head, and slender branchlets coated at first with hoary tomentum, becoming in their first winter ashy gray or light or dark reddish brown and usually pubescent or tomentose; more often an intricately branched rigid shrub, with stout stems covered by pale gray bark and usually 6°—8° high, often forming dense thickets. Winter-buds ellipsoidal, generally acute, 1/16′—⅛′ long, with thin pale red often pilose and ciliate scales. Bark of the trunk bright brown and scaly.
Distribution. California; western slopes of the central Sierra Nevada; common on the coast ranges south of San Francisco Bay and on the islands off the coast of the southern part of the state, ranging inland to the borders of the Mohave Desert and to the cañons of the desert slopes of the San Bernardino and San Jacinto mountains, and southward into Lower California; arborescent only in sheltered cañons of the islands; the var. Alvordiana, in the San Emidio Cañon of the coast ranges of Kern County and on the San Carlos Range, Fresno County; north of San Francisco Bay replaced by the variety bullata Engelm. ranging to Mendocino County and to Napa valley.
× Quercus MacDonaldii Greene, a shrub or small tree with characters intermediate between those of Quercus dumosa and Q. Engelmannii, is usually considered a hybrid of these species. It occurs on Santa Cruz and Santa Catalina Islands, and in Santa Barbara, and Los Angeles Counties, California.
29. [Quercus virginiana] Mill. Live Oak.
