American linden or American Basswood (Tilia americana) is a medium to large upright deciduous tree often 50-70’ tall (maximum 135’) with a neatly rounded crown. Leaves are alternate, large (7”), heart-shaped (lopsided), and toothed along the margin (edge). The upper leaf is green, with a paler green underneath. Twigs are yellow-brown to brownish with a zig zag pattern. Bark is smooth on young trunks and dark grayish-brown with many long, narrow, flatter-topped ridges. The wood of American lindens is valued for hand-carving and turnery and is often used as interior trim, veneer, plywood, and furniture parks. Small greenish yellow flowers hang below pale leafy bract in early summer, becoming ¼” round nuts that ripe in fall. American linden is considered an excellent source of nectar by bee-keepers. The decaying leaves, rich in nitrogen and minerals, contribute to soil fertility.
Swedish born Carl Linnaeus, the originator of the binomial system of nomenclature, appropriately got his last name from the Linden. Carl’s father, Nils Ingemarsson, needed a last name to enroll in the university and decided to name himself after the large old tree on their farm. The tree a Linden or Tilia (in Latin) or Lind (in Swedish) (Blunt W., Linnaeus: The Compleat Naturalist, page 12). The Lindens are referred to in British literature as “lime” trees, a derivative of the word “Lind”.
Common name: American Linden; American Basswood
Scientific Name (order and family): Tilia americana L. (Malvales, Malvaceae)
Origin: Eastern North America
Habit: Broadly columnar; medium to large tree 50 to 70 feet tall
Trunk/Stem: Bark brown to gray, cracked into long scaly ridges; suckers common. Twigs zig-zag and brownish
Leaves: Deciduous, alternate, simple. Ovate to nearly rounded of heart-shaped with the leaf base asymmetric (one side extends deeper than the other); abruptly tapered at tip (acuminate); matte deep green above and paler glossy beneath; margins coarsely serrate with long pointed teeth.
Flowers: Monoecious. Pale yellow with five petals, fragrant; in pendulous clusters (panicles) of up to ten flowers in each cluster subtended by a characteristic long bract.
Fruits and Seeds: Rounded woody pale gray-green about 3/8 inch wide.