122 Nut % inch or less in width. Southwestern Me. south and 
west — American Chestnut, Chestnut, Costarica dentata 
(Marsh.) Borkh. 
122 Nut more than % inch in width. Only in cult.—European 
Chestnut, Costarica saliva Mill. 
Note :—The Chinquapin is native from New Jersey south¬ 
ward. It has burs less than 2 inches thick, almost always 
inclosing a single nut, and hairy under surfaces to the 
leaves. Certain Japanese Chestnuts are sometimes culti¬ 
vated in New England; these can usually be recognized 
by the very large bur, sometimes 3 or more inches thick, 
the very small but prominently bristle-tipped teeth of the 
leaf margin, and the usually rounded base of the blade. 
Oak —'Leaves simple, alternate. Fruit a nut (acorn) sur¬ 
rounded at the base by a cup composed of closely over¬ 
lapping scales. 
123 Leaves entire, without lobes or marginal teeth. Local at 
one station in eastern Mass.—Laurel Oak, Shingle Oak, 
Quercus imbricaria Mx. 
123 Leaves either lobed or toothed, or both—124 
124 Lobes or marginal teeth ending in a bristle^—125 
124 Lobes or marginal teeth not ending in a bristle—130 
125 Lower surface of mature leaves smooth or nearly so—120 
125 Lower surface of mature leaves hairy—120 
12G Cup covering about y z the acorn—127 
120 Cup shallow and broad, covering considerably less than l / z 
the acorn—128 
127 Inner (or upper) thin scales of the cup finely hairy and 
loosely overlapping. Buds pointed and hairy. Inner 
bark yellowish-orange, very bitter—Black Oak, Yellow- 
bark Oak, Yellow Oak, Quercus velniina Lam. 
127 Inner (or upper) thin scales of the cup smooth or essen¬ 
tially so, and closely overlapping. Buds blunt and 
smooth. Inner bark reddish, not bitter—Scarlet Oak, 
Quei'cus coccinea Muench. 
128 Acorn small, less than % inch long. Mass, southward 
—Pin Oak, Quercus palustris Muench. 
