694 TREES OF NORTH AMERICA 



flowered nearly sessile umbel-like corymbs, the staminate and pistillate in separate or in 

 the same cluster on the same or on different trees; calyx broad-campanulate, 5-lobed by 

 the partial union of the sepals, pilose on the outer surface near the base; corolla 0; stamens 

 7 or 8, with slender glabrous filaments, in the staminate flower nearly twice as long as the 

 calyx and in the pistillate flower shorter than the calyx; ovary obtusely lobed, pale green, 

 covered with long scattered hairs, minute in the sterile flower. Fruit glabrous, with con- 

 vergent or wide-spreading wings \'-\' long; seeds smooth, bright red-brown, \' long. 



A tree, sometimes 80 high, with a trunk frequently 3 in diameter, stout spreading or 

 often erect branches, and stout branchlets marked by oblong pale lenticels, orange-green 

 and pilose with scattered pale caducous hairs when they appear, orange or orange-brown 

 and lustrous during their first year, becoming dull pale gray-brown the following season. 

 Winter-buds sessile, ovoid, acute, ' long, with dark red-brown acute scales hoary-pubes- 

 cent on the outer surface and often slightly ciliate on the margins, and yellow puberulous 

 inner scales, |'-1' long at maturity. Bark of young stems and of the branches thin, 

 smooth, pale gray, becoming on old trunks thick, deeply furrowed, and sometimes almost 

 black. 



Distribution. Valley of the St. Lawrence River in the neighborhood of Montreal, 

 Quebec, southward to the valley of Cold River, New Hampshire, through western Vermont 

 and Massachusetts and northwestern Connecticut (near Salisbury, Litchfield County), 

 and westward through northern and western New York, southern Ontario, Ohio, the 

 southern peninsula of Michigan, Indiana, Illinois, and Iowa to southeastern Minnesota, 

 northeastern South Dakota, western and southern Missouri, eastern Kansas, and south- 

 ward through western Pennsylvania, West Virginia and eastern Kentucky; comparatively 

 rare near Montreal and in New England, more abundant farther west; almost entirely re- 

 placing Acer saccharum in Iowa, and the only Sugar Maple of South Dakota ; easily dis- 

 tinguished in summer by its heavy drooping leaves, and at all seasons of the year by the 

 orange color of the branchlets; the var. Palmeri in a single grove at Tunnel Hill, Johnson 

 County, Illinois; southern Indiana (Shelby, Putnam and Lawrence Counties), and in Clark, 

 Jackson and Dunklin Counties, Missouri; rare and local. 



Occasionally planted in the region where it grows naturally as a shade-tree. 



10. Acer leucoderme Small. Sugar Maple. 



Leaves usually truncate or slightly cordate at base, more or less deeply divided into 

 3-5 acute caudate-acuminate lobes coarsely and sinuately dentate or undulate, when they 

 unfold coated below with long matted pale caducous hairs, and at maturity thin, dark 

 yellow-green above, bright yellow-green and pilose-pubescent below, 2'-3^' in diameter; 

 often turning in the autumn bright scarlet on the upper surface before falling; petioles 

 slender, glabrous, I'-l^' in length. Flowers yellow, about f long, on slender, glabrous 

 pedicels, in nearly sessile clusters; calyx campanulate, glabrous or slightly villose, with 

 rounded ciliate lobes; corolla 0; stamens 7 or 8; filaments villose, longer than the calyx, 

 much shorter than the calyx in the pistillate flower; ovary villose; style elongated, with 

 short spreading lobes. Fruit villose, with long scattered pale hairs until nearly grown, 

 becoming glabrous at maturity, the wings wide-spreading or divergent, 5' |' long; seeds 

 smooth, light red-brown, about \' long. 



A tree, usually 20-25 high, with a trunk a foot in diameter, occasionally 40 high, with 

 a trunk 18'-20' in diameter, short slender branches forming a rather compact round-topped 

 head, and slender glabrous branchlets dark green when they first appear, becoming bright 

 red-brown and lustrous during their first summer, and marked by numerous small oblong 

 pale lenticels, gradually growing darker in their second year and finally light gray-green. 

 Winter-buds ovoid, acute, dark brown, glabrous, rather more than yV long, the inner 

 scales becoming bright crimson and very conspicuous when the tree is in flower. Bark 

 of young stems and large branches close, light gray or grayish brown, becoming near the 

 base of old trees dark brown or often nearly black and broken by deep furrows into narrow 

 ridges covered by closely appressed scales. 



