96 



FAGACEAE. 



In southern California it grows usually above 8000 feet altitude in 

 the San Gabriel and San Bernardino Mountains. 



2. QUERCUS L. Oak. 



Trees or shrubs with persistent or deciduous leaves 

 and small green or yellowish monoecious flowers, the 

 staminate numerous in slender mostly drooping aments, 

 the pistillate solitary in many-bracted involucres. 

 Staminate flowers subtended by caducous bracts, con- 

 sisting of mostly a 6-lobed campanulate perianth and 

 5-12 stamens with filiform filaments. Pistillate with an 

 urn-shaped or oblong 3-celled ovary; ovules 2 in each 

 cell; styles usually 3, short. Fruit (acorn) consisting 

 of the imbricated and more or less united bracts of the 

 involucre (cup), subtending or nearly enclosing the 

 1 -seeded coriaceous nut. 



Bark not scaly, smooth or on old trunks irregu- 

 larly ruptured; stigmas on slender styles; 

 scales of the cup thin and closely imbri- 

 cated; nut tomentose on the inner surface. 

 Black Oaks. 

 Leaves deciduous, large and divided into 



bristle-tipped lobes. 1. Q. kelloggii. 



Leaves evergreen, small and coriaceous. 



Acorns maturing the second autumn; 



leaves plane, bright yellow-green and 



glabrous beneath. 2. Q. wislizenii. 



Acorns maturing the first autumn; leaves 



convex, pale beneath with tufts of 



hairs in the axils of the principal veins. 3. Q. agrifolia. 



Bark scaly, and on large trees usually furrowed; 



stigmas broad and nearly or quite sessile; 



cups usually 



White Oaks. 



Acorns maturing 



tomentose on 



ith tuberculate scales. 



the 

 the 



second autumn; nuts 

 inner surface; leaves 



evergreen. 

 Acorns maturing the first autumn. 



Leaves deciduous, more or less lobed. 

 Leaves dark green above, deeply lobed. 

 Leaves blue green above; shallowly 

 lobed or merely wavy margined. 

 Leaves evergreen. 



Trees with shallowly furrowed bark. 

 Shrubs; bark covered with loose scales. 



4. Q. chrysolepis. 



5. Q. lohata. 



6. Q. douglasii. 



7. Q. engelmanni. 



8. Q. dumosa. 



I. Q. kelloggii Newb. A handsome tree 15-30 m. high, with a 

 trunk 1-1.5 m. in diameter; bark smooth, divided into broad ridges 



