276 TREES OF NORTH AMERICA 



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, becom- 

 ing 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 



Fig. 252 



pale gray bark and usually 6-8 high, often forming dense thickets. Winter-buds ellip- 

 soidal, generally acute, TV~~i' l n g 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 canons 

 of the desert slopes of the San Bernardino and San Jacinto mountains, and southward into 

 Lower California; arborescent only in sheltered canons of the islands; the var. Alvordiana y 

 in the San Emidio Canon 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. 



X 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. 



Leaves oblong, elliptic or obovate, rounded or acute at apex, gradually narrowed 

 and cuneate or Tarely rounded or cordate at base, usually entire with slightly revolute 

 margins, or rarely spinose-dentate above the middle, thin, dark green and lustrous on the 

 upper surface, pale and pubescent on the lower surface, 2'-5' long, \'-%\' wide, and in- 

 conspicuously reticulate-venulose, with a narrow yellow midrib, and few slender obscure 

 primary veins forked and united at some distance from the margins; gradually turning 

 yellow or brown at the end of the winter and falling with the appearance of the new leaves 

 in the spring; petioles stout, rarely more than \' in length. Flowers: staminate in hairy 

 aments 2'-3' long; calyx light yellow, hairy, divided into 5-7 ovate rounded segments; 

 anthers hirsute; pistillate in spikes on slender pubescent peduncles l'-3' long, their in- 

 volucral scales and ovate calyx-lobes coated with hoary pubescence; stigmas bright red. 

 Fruit usually in 3-5 fruited spikes or rarely in pairs or single on stout light brown puberu- 

 lous peduncles 1/-5' long; nut ellipsoidal or slightly obovoid, narrowed at base, rounded 

 or acute at apex, dark chestnut-brown and lustrous, about 1' long and \' thick, inclosed 

 for about one fourth its length in a turbinate light reddish brown cup puberulous within, 



