Trees with heart-shaped leaves, and how to tell them apart

Eastern redbud: small, smooth hearts

The tree most people mean when they ask about heart-shaped leaves is the eastern redbud. The NC State Plant Toolbox describes simple, alternate, heart-shaped leaves 3 to 5 inches long and about as wide, with smooth edges, a pointed tip and a swelling on the leaf stalk just below the blade. In early spring, from March to May, clusters of small pink to purple pea-like flowers open directly on new stems and older branches, before the leaves. Flat brown pods 2 to 4 inches long follow and can hang on into winter.

Redbud is a small tree, 20 to 30 feet tall in NC State's profile, native from Ontario and Michigan south to Florida and west to Nebraska and New Mexico. If the leaves are smooth-edged hearts on a small tree, check for the pods and the swollen stalk joint.

American linden (basswood): big, toothed and lopsided

If the heart is toothed and lopsided, with one side of the base lower than the other, look at American linden, also called basswood. According to the NC State profile, the leaves are alternate, ovate to heart-shaped, unequal at the base and coarsely serrated, up to 10 inches long and 3 to 6 inches wide, dark green above and matte gray underneath.

Linden has a clue no other tree here shares: its fragrant yellow flowers (May to July) and then its pea-sized, downy nutlets hang from a stalk attached to the middle of a leaf-like bract that acts as a wing. One of those bracts on the ground under a tree with heart-shaped leaves is close to proof. American linden grows wild from New Brunswick to Florida, west to Texas and north to Manitoba.

Katsura: small rounded hearts in pairs

Katsura is a planted tree native to China and Japan. The NC State profile describes leaves 2 to 4 inches long, broadly heart-shaped or kidney-shaped, with veins spreading from the base like fingers and scalloped to finely toothed edges. They grow opposite or nearly opposite on short side shoots. New leaves open reddish-bronze to purple, turn blue-green in summer and yellow to apricot in fall.

The best test comes in autumn: NC State notes that the decaying leaves smell like caramel, burnt sugar or cotton candy. No other tree on this list does that.

Catalpa and princess tree: the giant hearts

Two trees carry heart-shaped leaves the size of a dinner plate, and they are easy to confuse.

Northern catalpa. The NC State profile describes light green leaves 6 to 12 inches long, whorled (three at a node) or opposite, smooth-edged, pointed at the tip and heart-shaped at the base, with soft hairs underneath. In late spring to early summer, upright clusters of white, bell-shaped flowers with yellow and purple markings inside appear, followed by cigar-like pods up to 22 inches long that ripen dark brown in fall. It is native to the eastern and central United States. Southern catalpa looks similar; NC State separates the two by smell, since crushed southern catalpa leaves have a fetid odor and northern catalpa leaves a "green" one. The flowers make catalpa one of the late trees with white flowers, and the catalpa page covers the tree through the year.

Princess tree (paulownia). The NC State profile describes opposite, oval or heart-shaped leaves 5 to 12 inches long with velvety hairs on both sides, and notes that they resemble catalpa leaves. The difference shows in flower and fruit: princess tree blooms in spring with upright clusters, up to 14 inches long, of pale violet, foxglove-like flowers, and its fruit is a woody, egg-shaped capsule only 1 to 1.5 inches long, holding thousands of tiny winged seeds. NC State lists princess tree as invasive in North Carolina.

Quick test: long, thin pods mean catalpa; clusters of short, pointed, woody capsules mean princess tree. Velvety leaves on both sides also point to princess tree.

The tree with three leaf shapes: sassafras (and mulberry)

If one tree carries heart-shaped or oval leaves alongside mitten-shaped and three-lobed ones, it is almost always a sassafras. The USDA Forest Service describes sassafras as an aromatic tree "with three distinctive leaf shapes: entire, mittenshaped, and threelobed". The Forest Service calls the whole tree aromatic, so crush a leaf or scratch a twig and smell it. Greenish-yellow flowers appear in March and April as the leaves unfold.

Mulberries do the same trick with toothed leaves. The NC State profile of red mulberry describes heart-shaped, thin, toothed leaves 3 to 5 inches long that range from unlobed to deeply lobed; lobed leaves are more frequent on new shoots, unlobed ones in the crown. The underside has fine hairs and feels soft. White mulberry, an Asian species now naturalized across much of the United States, has alternate, toothed leaves that are unlobed, mitten-shaped or three-lobed; NC State says their glossy upper surface distinguishes them from red mulberry. The mulberry page separates red, white and fruitless mulberries.

How to work through it

1. Run a finger along the edge. Smooth: redbud, catalpa, princess tree. Toothed or scalloped: linden, katsura, mulberry.
2. Check the arrangement. Alternate: redbud, linden, mulberry, sassafras. Opposite or whorled: katsura, catalpa, princess tree.
3. Measure. Under 5 inches: redbud, katsura, red mulberry. Up to 10 inches: linden. Up to 12 inches: catalpa (soft hairs underneath) and princess tree (velvety on both sides).
4. Look for the extra clue. Pods, bracts, a burnt-sugar smell, mixed leaf shapes.

For leaf shapes, margins and arrangement in general, see how to identify trees by their leaves.

When to use a photo

A single photo of a typical leaf, ideally with a pod, flower or bract in the frame, gives Tree Identifier enough to suggest a name. Eastern redbud, sassafras, white mulberry, princess tree and southern catalpa are among the species in the app's Collection. Tree Identifier does not show look-alikes, so if it says catalpa, check the pods against the princess-tree test above, or ask the follow-up chat how the two differ.