FAGACEAE 



Canyon Live Oak 



Quercus chrysolepis Liebm. 



HABIT. A shrub to medium-sized tree 60-80 feet high and 

 1-5 feet in diameter (max. 100 by 12 feet); usually dividing 

 above the ground into large, horizontal branches; large, spread- 

 ing crown; forming dense thickets on dry slopes. 



LEAVES. Persistent 3-4 years; oblong-ovate to elliptic; 

 1-4 inches long; mostly entire on old trees and sinuate-dentate 

 on young trees, or both forms appearing together; revolute 

 margins; leathery; bright yellow-green and glabrous above; 

 tawny-tomentose, becoming glabrous and blue-green below. 



FRUIT. Maturing in 2 years; sessile or nearly so; acorn Yi- 

 2 inches long, chestnut-brown, ellipsoidal to ovate; enclosed 

 at base in thick, shallow cup with hairy to golden-woolly scales; 

 inner surface of nut shell woolly; kernel bitter. 



TWIGS. Slender; brown to gray; woolly, sometimes becom- 

 ing smooth. Winter buds: Yq inch, ovoid, acute, chestnut- 

 brown. 



BARK. Rather thick {Y^-lYi inches); gray-brown, tinged 

 with red; smooth except for small scales on old trunks. 



SILVICAL CHARACTERS. Tolerant when young; long- 

 lived; canyon walls to dry mountain slopes; passes into the 

 variety palmeri (Engelm.) Sarg. in the Southwest. 



* * * 



SiLVERLEAF OaK 



Quercus hypoleucoides A. Camus {Quercus hypoleuca Engelm.) 



HABIT. A shrub or small tree 20-30 feet high (rarely 60 

 feet) and 10-15 inches in diameter; narrow, rounded crown. 



LEAVES. Persistent until appearance of new leaves; lanceo- 

 late to elliptic; 2-4 inches long; entire or with few coarse teeth 

 near apex; revolute margins; leathery; dark yellow-green and 

 lustrous above, woolly below. 



FRUIT. Maturing in 2 years; sessile or short-stalked; acorn 

 Y2~V'i inch long, chestnut-brown, ovoid; enclosed for Y?, of 

 its length in thick cup with thin, brown, silvery-hairy scales; 

 inner surface of nut shell woolly; kernel bitter. 



TWIGS. Stout; red-brown. Winter buds: Yq inch long, brown, 



BARK. Rather thick (H-1 inch); nearly black; deeply fur- 

 rowed into broad, thick-scaled ridges. 



SILVICAL CHARACTERS. Intolerant; on dry, low moun- 

 tain sites. 



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