3i8 



The Oaks 



they are thick, stiff and leatheiy, dark green, ver}^ shining, smooth or sHghtly 

 hair}' with raised midrib above; paler, dull, smooth or hairy, at least along the 



prominent midrib, and obscurely net- 

 veined beneath, persistent until spring 

 when the new leaves begin to unfold. 

 The leaf-stalk is stout and shghtlv 

 hair}% 2 to 5 mm. long. The stami- 

 nate flowers are in hairy catkins 5 to 

 7.5 cm. long; their calyx, which is 5- 

 to 7-lobed, is haiiT and hght yellow. 

 The pistillate flowers are sessile or on 

 stout hair)' stalks, the involucres also 

 haiiy; styles sHghtly spreading. The 

 fruit ripens from July to September of 

 the first season, is sessile or nearly so; 

 nut oblong or narrowly ovoid, 12 to 20 

 mm. long, dark brown when ripe, the 



Fig. 271. Emon-'s Oak. 



apex hair\'; shell thin, white downy inside; cup hemispheric, 10 to 12 mm. across, 

 hair}- inside, embracing about one third of the nut, its scales ovate, pointed, light 

 bro\\'n and hair}'. 



The wood is rather soft, strong but brittle, close-grained, dark brown; its 

 specific gravity is about 0.93. The sweet nuts are of commercial importance to 

 the Indians and Mexicans of our southern border, where they are sold for food 

 in the markets under the name of biotis. 



35. TEXAN WHITE OAK Quercus breviloba (Torrey) Sargent 

 Quercus ohtusijolia breviloba Torrey. Quercus Durandii Sargent, not Buckley 



Usually a shrub, this oak sometimes 

 becomes a tree 9 meters tall, with a 

 trunk diameter of 4 dm. It grows in 

 hmestone soil in central and western 

 Texas and adjacent Mexico, and as a 

 shrub forms dense thickets. It is also 

 called White oak. Pin oak, and Shin 

 oak. 



The trunk is usually divided very 

 near the base into several principal 

 branches. The bark is about 6 mm. 

 thick, grayish white or gray-brown, 

 separating into thin, loose elongated 

 scales. The twigs are slender, hain,', be- 

 coming smoother and gray. The buds fig. 272. Texan White Oak. 



