76 Bulletin of the University of Texas 



trunk in loose, elongated plates. Leaves obovate or oblanceo- 

 late, >vith 5-7 shallow lobes, wedge-shaped at base, bluish green 

 and shining above, paler and hairy beneath, remaining on the 

 tree until the new leaves of the following spring unfold. 

 Acorns sessile or very short stalked ; nut ovoid, cup saucer- 

 shaped, scales appressed, encloing about one-fourth of the nut. 



West Texas and Mexico. Most abundant in dry limestone 

 soil. 



The wood is used for fuel. 



14. Quercus undulata Torrey. Shin oak. A shrub or 

 small tree sometimes 25-30 high with thin scaly gray bark, 

 and reddish brown twigs. Leaves oval to oblong l'-3' 

 long, &'- %' wide entire or with wavy sometimes toothed 

 margin, smooth and lustrous above, yellowish brown beneath, 

 peris: ut. Fruit ripening th( first season, solitary or in pairs, 

 sessile or stalked. Acorn oval %'-!' long enclosed for about 

 one-third its length in the cup. 



On dry ridges and cliffs, Colorado, New Mexico, Arizona, 

 Utah, Nevada, western Texas, and Mexico. 



15. Quercus oblongifolia Torrey. Blue Oak. A small tree 

 usually not over 30 in height, and ]8'-20' in diameter. It 

 branches freely to form a rounded symmetrical crown. The 

 bark is ^'-l^' thick, light gray, scaly, the scales are close, 

 regular. Leaves oblong, ovate or oblanceolate, entire or 

 notched at the apex of the undulate margin, bluish green per- 

 sistent until the new leaves of the following spring. Acorns 

 are sessile or stalked; nut ovoid, dark brown, %'-%' long, 

 about one-third enclosed in the hemispheric, hairy cup. 



Chisos Mountains of West Texas, extending into Mexico, 

 Arizona, and New Mexico. The trees are small and are only 

 used for fuel. 



16. Quercus hypoleuca Englemann. White Leaf Oak. A 

 shrub or small tree usually not over 30 -40 high with round 

 top, spreading slender branches, and rough fissured dark bark. 

 Leaves lanceolate, elliptic or oblong lanceolate, 2'-4' long, 

 %'-!' wide, with thickened margins, entire or some of them 

 slightly toothed, bristle tipped, yellowish green and lustrous 

 above, whitish and wooly beneath. Fruit ripening in the sec- 



