The Oaks 



D. Lobes of leaves acute. (Q. acuminata) yellow oak 

 DD. Lobes of leaves rounded. 



E. Bark dark brown, deeply furrowed. 



(Q. Frinus) chestnut oak 

 EE. Bark light grey, scaly. 



F. Limbs sheading bark in large flakes; 

 acorns on long stalks. 



(Q. platanoides) swamp white oak 

 FF. Limbs not shedding bark in flakes; acorns 

 sessile or on short stalks. 



{Q. Michauxii) basket oak 



The Blue Oak, or Mountain White Oak (Quercus Doug- 

 lasii, Hook, and Arn.), is a striking and beautiful feature of the 

 landscape of northern and central California. Silvery grey bark 

 and pale blue foliage, deepened by greenish leaf linings, and 

 lightened by their silvery pubescence! No wonder the blue oak 

 attracts attention whether it stands among the scattered groves 

 of California white oak in the broad valleys — a fine, round-headed 

 tree — or climbs the western slopes of the Sierras till it dwindles to 

 a shrub at an altitude of 4,000 feet. It is strangely variable in the 

 shape of its leaves and fruit. Its leaf may have deep lobes like 

 other white oaks, or it may have scarcely any noticeable waves; 

 some leaves are entire, some have pointed, even spiny-tipped lobes 

 like those of the black oaks. The blue of them, however, is a 

 dependable characteristic; also the silky leaf linings. 



The acorns are very numerous, and so vividly green in 

 summer that they often overcome much of the blue of the foliage 

 until they take on their rich, chestnut brown. The nut often 

 bulges above the saucer-like cup as if too large for it; often it is 

 elongated into a pencil shape. 



The wood is too brittle and the sap wood too thick for use in 

 building. It is an excellent fuel. 



California White Oak {Quercus lobata, Nee.) — A large, 

 graceful tree with stout trunk dividing near the ground, with 

 spreading top and pendulous branches, making a broad dome, 

 80 to 100 feet high, and 1 50 to 200 feet in diameter. Bark brown- 

 ish grey, scaly, with shallow furrows, and ridges broken into 

 plates; twigs hoary, grey or reddish brown. H^ood hard, fine 

 grained, brittle and hard to season. Buds ovate, small, pubescent. 

 Leaves alternate, variable, oblong or obovate, 2 to 4 inches long, 

 deeply 7 to i i-lobed, thin, firm, pubescent, paler beneath; petioles 



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