Culture
Easily grown in average, medium moisture, well-drained soils in full sun to part shade. Tolerates some drought. Prefers moist, fertile, well-drained loams. Generally intolerant of air pollution and urban conditions.
Noteworthy Characteristics
Tilia americana, commonly called American basswood or American linden, is a medium to large deciduous tree which typically grows to 50-80’ (infrequently to over 100’) tall with an ovate-rounded crown. It is native to a variety of habitats from Quebec to the southeastern corner of Manitoba and far eastern North Dakota south to Oklahoma, Tennessee and North Carolina, with concentrations in forested areas of the Appalachian Mountains and along the Ohio River Valley to Missouri. Trees are found in both dry upland areas as well as moist, low woods. In Missouri, this tree typically occurs in rich woods, slopes, bluff bases and along streams throughout the State (Steyermark). This tree is noted for its (a) cymes of fragrant, pale yellow, late spring flowers, (b) small nutlets which follow the flowers and ripen by late summer, (c) mucilaginous sap, (d) noticeable winter buds, and (e) large ovate dark green leaves (to 6” long) with acuminate tips, serrate margins, often silvery undersides and uneven cordate bases. Flowers bloom in June in 5-10 flowered cymes. Each cyme droops from a showy, papery, narrow, leaf-like bract (to 5” long) where it is attached to the bract at a point somewhere between the base and midpoint. When a tree is in full bloom, bees often visit in such abundant numbers that humming can be heard many feet from the tree. Honey made from the nectar of these flowers is a prized gourmet item. Flowers have also been used to make tea. Syrup can be made from the sweet tree sap. Fall color is an undistinguished pale green to pale yellow. Winter twigs and buds are sometimes tinged with red.
Var. heterophylla, formerly known as Tilia heterophylla, is very similar to the straight species except for (1) leaf undersides are whitish, (2) flowers are slightly smaller but arranged in larger 10-25 flowered cymes, and (3) native range is more southern (southwestern Pennsylvania and Maryland along the Ohio River to Missouri south to Mississippi and North Carolina).
Variety name of heterophylla comes from the Latin words hetero meaning different and phylum meaning leaf in reference to the distinctive leaves.
A tree of this variety at the Missouri Botanical Garden measuring 103’ tall has been declared National Champion (factors include height, circumference and crown spread) by the not-for-profit organization American Forests.
Genus name comes from the Latin name for the linden or lime tree, known in southern Sweden as linn and the origin of the name Linnaeus.
Specific epithet is in obvious reference of the native territory of this species.
The common name of basswood is derived from bastwood, in reference to the tough inner bark (bast) which has been used to make rope and mats. Trees are commercially harvested, particularly in the Great Lakes region, for their light wood which is used to make such items as furniture, shipping crates, boxes, and veneer. Common name of linden plus the family name of Linneaus (famous Swedish botanist Carl Linnaeus was ennobled as Carl von Linne) both derive from lind which is the Swedish word for a linden tree.
Problems
No serious insect or disease problems. Verticillium wilt is infrequent, but can be fatal. Powdery mildew, leaf spots and cankers may occur. Insect visitors include borers, beetles, lacebugs, caterpillars and scale. Spider mites can do significant damage, particularly in hot, dry periods.
Uses
Handsome ornamental shade tree or street tree. Although well adapted to Missouri’s climate, this tree is generally intolerant of city conditions. Some of the European lindens (see T. cordata, T. tomentosa and T. x europaea) may make better selections for urban areas.