KEY TO THE SPECIES OF OAKS 



I, Leaves turning brown in the fall of the first year, neither thick 

 and leathery nor spiny-toothed. 



II. Leaves or leaf lobes not bristle-tipped; acorn maturing in 1 

 year, usually sweet ; nut shell smooth on inside . WHITE OAKS 



III. Leaves deeply lobed or rarely entire 



True White Oaks, p. 1 75. 



III. Leaves coarsely toothed or shallowly lobed 



Chestnut Oaks, p. 1 76. 



II. Leaves or leaf lobes commonly bristle-tipped; acorn maturing 



in 2 years, usually bitter ; nut shell woolly on inside 



RED OAKS 



IV. Leaves lobed, rarely broadly ovate and entire 



True Red Oaks, p. 1 76. 



IV. Leaves entire and mostly narrow. . .Willow Oaks, p. 178. 



I. Leaves remaining green on the tree at least until the new leaves 



appear the following spring, usually thick and leathery, margins 



entire or spiny-toothed LIVE OAKS, p. 178. 



True White Oaks 



\. Eastern Species (east of the Rocky Mountains). 

 2. Leaves entire or slightly lobed. 



3. Acorns enclosed only at base by thin cup. 



4. Acorn %-! inch long; leaves mostly blue-green; shrubby; 



Western Texas and Oklahoma 



Q. durandii var. brevilobata (Torr.) Palmer, Bigelow Oak 



4. Acorn Vi-Vi inch long; leaves yellow-green; large tree; 

 South Carolina to Florida, west to Texas and Arkansas 

 Q. durandii Buckl., Durand Oak 



3. Acorns enclosed V4-% length in thick cup. 



5. Acorn Yi-Vi inch long; leaves blue-green; western Texas 

 and Oklahoma Q. mohriana Buckl., Mohrs Oak 



5. Acorn % inch long; leaves yellow-green; South Carolina 



to Florida Q. chapmanii Sarg., Chapman Oak 



2. Leaves more or less deeply lobed. 



6. Acorns enclosed Vi or more of length in cup; leaves 5-9 

 lobed. 

 7. Acorn cup conspicuously fringed on margin; leaves 



nearly divided in two by deep sinuses 



Q. macrocarpa, Bur Oak, p. 181. 



7. Acorn cup not fringed and nearly covering acorn; leaves 

 irregularly lobed Q. lyrata, Overcup Oak, p. 183. 



6. Acorns enclosed less than Vi of length in unfringed cup. 



8. Leaves regularly and usually deeply 7-9 lobed, glabrous 

 below Q. alba, White Oak, p. 181. 



8. Leaves typically cross-shaped, 5-lobed, red-woolly below 



Q. stellata, Post Oak, p. 183. 



1. Western Species (Rocky Mountain and Pacific Coast regions). 

 9. Leaves undulately lobed with acute lobes or entire, blue-green, 

 l-lVl inches long; acorn enclosed only at base in cup. 

 10. Leaves not spiny-toothed; Colorado to Nevada and south 



Q. undulata Torr., Wavyleaf Oak 



10. Leaves spiny-toothed; Texas to Arizona 



Q. pungens Liebm., Sandpaper Oak 



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