=Bark.=--Bark of trunk when young, smooth, yellowish-green, in old trees becoming grayish-brown and ridgy; smaller branchlets greenish-yellow; season's shoots pale green or sometimes reddish-purple, smooth and shining or sometimes glaucous. =Winter Buds and Leaves.=--Buds small, ovate, enclosed in two dull-red, minutely pubescent scales. Leaves pinnately compound, opposite; leaflets usually 3, sometimes 5 or 7, 2-4 inches long, 1-1/2-2-1/2 inches broad, light green above, paler beneath and woolly when opening, slightly pubescent at maturity, ovate or oval, irregularly and remotely coarse-toothed mostly above the middle, 3-lobed or nearly entire; apex acute; base extremely variable; veins prominent; petioles 2-3 inches long, enlarging at the base, leaving, when they fall, conspicuous leaf-scars which unite at an angle midway between the winter buds. =Inflorescence.=--April 1-15. Flowers appearing at the ends of the preceding year's shoots as the leaf-buds begin to open, small, greenish-yellow; sterile and fertile on separate trees,--the sterile in clusters, on long, hairy, drooping, thread-like stems; the calyx hairy, 5-lobed, with about 5 hairy-stemmed, much-projecting linear anthers; pistil none: the fertile in delicate, pendent racemes, scarcely distinguishable at a distance from the foliage; ovary pubescent, rising out of the calyx; styles long, divergent; stamens none. =Fruit.=--Loose, pendent, greenish-yellow racemes, 6-8 inches long, the slender-pediceled keys joined at a wide angle, broadest and often somewhat wavy near the extremity, dropping in late autumn from the reddish stems, which hang on till spring. =Horticultural Value.=--Hardy throughout New England; flourishes best in moist soil near running water or on rocky slopes, but accommodates itself to almost any situation; easily transplanted. Plants of the same age are apt to vary so much in size and habit as to make them unsuitable for street planting. An attractive tree when young, especially when laden with fruit in the fall. There are several horticultural varieties with colored foliage, some of which are occasionally offered in nurseries. A western form, having the new growth covered with a glaucous bloom, is said to be longer-lived and more healthy than the type. [Illustration: PLATE LXXVII.--Acer Negundo.] 1. Winter buds. 2. Branch with sterile flowers. 3. Sterile flower. 4. Branch with fertile flowers. 5. Fertile flower. 6. Fruiting branch. TILIACEAE. LINDEN FAMILY. =Tilia Americana, L.= BASSWOOD. LINDEN. LIME. WHITEWOOD. =Habitat and Range.=--In rich woods and loamy soils. Southern Canada from New Brunswick to Lake Winnipeg. Throughout New England, frequent from the seacoast to altitudes of 1000 feet; rare from 1000 to 2000 feet. South along the mountains to Georgia; west to Kansas, Nebraska, and Texas.