How to Identify American Basswood Trees

The American basswood (Tilia americana) is a subspecies within the linden (Tiliacea) family. There are several varieties with separate names: The white basswood (var. heterophylla) is found from Missouri to Alabama, while the Carolina basswood (var. caroliniana) is found from Oklahoma to North Carolina and south to Florida. This fast-growing deciduous tree is among the largest in eastern and central North America. 

Basswood flowers produce an abundance of nectar from which choice honey is made with a distinctive flavor. In fact, in some parts of its range basswood is known as the bee tree, and can even be identified by the honeybee traffic. This is because basswood blooms in midsummer when few other trees are blooming. An abundance of nectar attracts other pollinators, too, including moths and butterflies.

Description and Identification

American basswood’s family, linden, contains about 30 species of trees that are native throughout most of the temperate Northern Hemisphere. The name basswood comes from Indigenous Americans using the tree's tough, fibrous inner bark, or "bast," to make cords and ropes. Newcomers to North America started calling it "bastwood," which led to its current name.

Bark

When identifying the American basswood, look at its bark first. Basswood's bark can be light to silvery gray and fairly smooth on young trunks. As the tree ages, its bark turns darker, sometimes almost black, and develops deeper and longer narrow ridges. American basswoods also have large root systems, aiding their substantial growth. 

Leaves

You can also identify this tree by its leaves. Basswood's asymmetrical and lopsided heart-shaped leaf is the largest of all broadleaf tree leaves; it is nearly as wide as it is long, between 5 and 8 inches.

The rich green upper side of the leaf contrasts the underleaf's paler green to almost-white color. You should be able to see some hairs on the surface. These leaves have slightly serrated edges and a short point. Take a close look at the twigs, and you'll see them zigzag between oval buds.

Size and Shape

The tree adds between 12 and 24 inches in height annually and, at maturity, can reach heights of 75 to 130 feet. American basswood features a round top and dense foliage, sprouting from the base of its trunk and forming several characteristic clumps. It is short-lived compared to other similar trees like hard maple or red oak.

Flowers and Seeds

The basswood's small yet highly fragrant yellowish-green flowers are uniquely attached and hang together with a grayish-brown fruit under a leaflike bract (described as "a narrow elliptical, life-like wing").

The seeds are contained within the hard, dry, hairy, nutlike fruit, which is quite visible during the fruiting season. When the bract releases from the branch, it "acts as a helicopter wing and carries the seeds away in a breeze."

Native Range and Habitat

American basswood can be identified in parts of the northeastern and central United States, including but not limited to Maine, Iowa, New Jersey, Michigan, and West Virginia. It is also found in Manitoba, Quebec, New Brunswick, and Ontario.

American basswood thrives in mesic regions but tolerates sandier soils, as well. The tree is often found in soil that falls between 4.5 to 7.5 in pH, according to the USDA. It prefers cold winters and warm summers.

Uses

The leaves of the American basswood are said to be high in nutrients and commonly used in tea for their medicinal properties. According to the Lady Bird Johnson Wildflower Center, some have also used basswood flowers in baths to treat cold symptoms and in beauty products. In addition, the leaves can make great mulch; mow them with a lawnmower and leave the remnants on the lawn to nourish it.

Because basswood has soft wood, it can be used for hand carving, and the inner bark is a source for rope baskets, mats, nets, and other items.