The Oaks 



II. THE BLACK OAK GROUP 



Acorns biennial; leaf lobes spiny tipped; bark dark. 



KEY TO SPECIES 



A. Pacific coast species. 



B. Leaves holly-like, evergreen. 



C. Young growth golden tomentose; branchlets pen- 

 dulous. {Q. chrysolepis) mountain live oak 

 CC. Young growth hoary; branchlets erect. 



D. Acorns elongated ; leaves pubescent ; fruit annual. 



(Q. agrifoha) California live oak 

 DD. Acorns ovate; leaves smooth. 



(Q. WisUieni) highland oak 

 BB. Leaves not holly-like, deciduous. 



(Q. Calijornica) kellogg's oak 

 AA. Eastern species. Deciduous. 



B. Leaves pinnately toothed and cleft by deep sinuses, petiole 

 slender. 

 C. Acorn cup shallow, broader than high. 



D. Tree pyramidal; branches with pin-like spurs. 



{Q. palustris) pin oak 

 DD. Tree spreading; acorn large, in smooth, shallow 

 saucer {Q. rubra) red oak 



DDD. Tree of oblong head; acorn cup greyish, downy. 



{Q. Texana) texan red oak 

 CC. Acorn cup hemispherical, as high as broad. 



D. Leaves thin, glabrous beneath; acorn cup drawn 

 in at top. {Q. coccinea) scarlet oak 



DD. Leaves coarse, tufted with rusty hairs below; 

 acorn cup not drawn in at top. 



{Q. velutina) black oak 

 DDD. Leaves firm, pale greyish downy beneath; acorn 

 cup drawn in at top. 

 E. Lobes 5 to 7, lanceolate or sickle-like. 



F. Leaves thin, 6 to 7 inches long; lobes 

 entire (Q. digitata) Spanish oak 



FF, Leaves thick, 3 to 12 inches long; lobes 

 toothed. (Q. Catesbm) turkey oak 



EE. Lobes 3 to 5, broad, spiny tipped. 



(Q. nana) bear oak 

 BB. Leaves 3 to 5-lobed at apex or nearly entire, on short 

 petioles, becoming glossy. 

 C. Tree squat, contorted, spreading. 



(Q. Marilandica) black jack 

 CC. Tree slender, tall, graceful. (Q. nigra) water oak 



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