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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.
Habit. —A large tree, 5O-75 feet high, rising in the upper valley of the Connecticut river to the height of 100 feet; trunk 2-4 feet in diameter, erect, diminishing but slightly to the branching point; head, in favorable situations, broadly ovate to oval, rather compact, symmetrical; branches mostly straight, striking out in different trees at varying angles; the numerous secondary branches mostly horizontal, slender, often drooping at the extremities, repeatedly subdividing, forming a dense spray set at broad angles. Foliage very abundant, green when fully grown, almost impervious to sunlight; the small creamy flowers in numerous clusters; the pale, odd-shaped bracts and pea-like fruit conspicuous among the leaves till late autumn.
Bark. —Dark gray, very thick, smooth in young trees, later becoming broadly and firmly ridged; in old trees irregularly furrowed; branches, especially upon the upper side, dark brown and blackish; the season's shoots yellowish-green to reddish-brown, and numerously rough-dotted. The inner bark is fibrous and tough.
Winter Buds and Leaves. —Leaf-buds small, conical, brownish red, contrasting strongly with the dark stems. Leaves simple, alternate, 4-5 inches long, three-fourths as wide, green and smooth on both sides, thickish, paler beneath, broad-ovate, one-sided, serrate, the point often incurved; apex acuminate or acute; base heart-shaped to truncate; midrib and veins conspicuous on the under surface with minute, reddish tufts of down at the angles; stems smooth, 1-1½ inches long; stipules soon falling.
Inflorescence. —Late June or early July. In loose, slightly fragrant, drooping cymes, the peduncle attached about half its length to a narrowly oblong, yellowish bract, obtuse at both ends, free at the top, and tapering slightly at the base, pedicels slender; calyx of 5 colored sepals united toward the base; corolla of 5 petals alternate with the sepals, often obscurely toothed at the apex; 5 petal-like scales in front of the petals and nearly as long; calyx, petals, and scales yellowish-white; stamens indefinite, mostly in clusters inserted with the scales; anthers 2-celled, ovary 5-celled; style 1; stigma 5-toothed.
Fruit. —About the size of a pea, woody, globose, pale green, 1-celled by abortion: 1-2 seeds.
Horticultural Value. —Useful as an ornamental or street tree; hardy throughout New England, easily transplanted, and grows rapidly in almost any well-drained soil; comes into leaf late and drops its foliage in early fall. The European species are more common in nurseries. They are, however, seriously affected by wood borers, while the native tree has few disfiguring insect enemies. Usually propagated from the seed. A horticultural form with weeping branches is sometimes cultivated.
Note. —There is so close a resemblance between the lindens that it is difficult to distinguish the American species from each other, or from their European relatives.
American species sometimes found in cultivation:
Tilia pubescens, Ait. , is distinguished from Americana by its smaller, thinner leaves and densely pubescent shoots.
Tilia heterophylla, Vent. , is easily recognized by the pale or silver white under-surface of the leaves.
There are several European species more or less common in cultivation, indiscriminately known in nurseries as Tilia Europæa . They are all easily distinguished from the American species by the absence of petal-like scales.
| 1. Winter buds. |
| 2. Flowering branch. |
| 3. Flower enlarged. |
| 4. Pistil with cluster of stamens, petaloid scale, petal, and sepal. |
| 5. Fruiting branch. |