Catalpa Tree Identification Guide

Key Identifying Features

Catalpa trees (Catalpa bignonioides, the Southern Catalpa, and C. speciosa, the Northern Catalpa) are easy to spot thanks to three standout traits:

• Huge heart-shaped leaves up to 25-30 cm long
• Showy clusters of white trumpet flowers in early summer
• Long, narrow, cigar- or bean-like seed pods that dangle through winter

They are medium-sized deciduous trees, typically 10-18 m tall, with a broad, irregular, spreading crown.

Leaves & Stems

The leaves are the most reliable feature year-round. They are large, broadly heart-shaped (ovate to cordate), with a pointed tip and smooth (untoothed) margins. Leaves are arranged in whorls of three or in opposite pairs — a useful detail, since most large-leaved trees are alternate. The upper surface is bright green; the underside is paler and often slightly hairy. Crushed leaves of C. bignonioides give off a faintly unpleasant smell.

Twigs are stout, and the leaf scars are large and rounded. The bark is grayish-brown, ridged or scaly. New growth appears late in spring, so a leafless Catalpa in May is normal.

Flowers & Fruit

• Flowers appear in June-July in large upright pyramidal panicles. Each bloom is a 2-5 cm white bell with frilled lobes, marked inside with yellow stripes and purple/brown spots and freckles — orchid-like and fragrant.
• Fruit is the signature feature: long, slender, hanging pods 20-45 cm long (longest in Northern Catalpa), green ripening to dark brown. They split open to release flat, papery, fringe-winged seeds. The pods persist on bare branches all winter, giving the tree the nicknames "Indian bean tree" and "cigar tree."

How to Tell It Apart from Look-Alikes

• Northern vs. Southern Catalpa: Northern (C. speciosa) has larger leaves with a long-pointed (taper) tip, fewer/larger flowers with fainter spotting, and thicker-walled pods; Southern (C. bignonioides) has more densely spotted flowers and thinner pods. Crushed Southern leaves smell unpleasant; Northern leaves are nearly odorless.
• Paulownia (Empress Tree) also has huge heart-shaped leaves but bears purple foxglove-like flowers and egg-shaped woody capsules, not long bean pods.
• Basswood/Linden has heart-shaped leaves but they are toothed and the tree bears small fragrant flowers with a leafy bract, not trumpets or pods.

Where You'll Find It

Native to the central and southeastern United States, Catalpas are widely planted as ornamental and street/park trees across temperate North America and Europe. They thrive in moist soils along streams, fencerows, and disturbed ground, and tolerate urban conditions well.

Quick ID Checklist

• Very large heart-shaped leaves, untoothed, in whorls or pairs
• White frilled trumpet flowers with yellow and purple markings (early summer)
• Long, slender bean-like pods hanging into winter
• Stout twigs with large round leaf scars
• Broad, irregular spreading crown; leafs out late