Northern Catalpa, Cigar Tree (Catalpa speciosa)

by Martin (Mort) Schmidt for Simply Living

Northern Catalpa (Catalpa speciosa herein, simply “Catalpa”), is one of our most distinctive trees. Catalpa has one of the largest simple leaves of any American tree, and its long cigar-like seed pods make it easily recognizable throughout the year. Native not to Ohio, but to the Mississippi Valley near the confluence with the Ohio River (depending on who you believe), Catalpa has been widely planted for its distinct leaves and attractive flowers. 

Catalpa leaves are heart-shaped (chordate), and often as much as a foot long, with 4- to 6-inch stems. Few trees that grow in Ohio have larger leaves. Among them are Kentucky Coffeetree (Gymnocladus dioicus) and the non-native Tree of Heaven (Ailanthus altissima), but they have compound leaves with numerous smaller leaflets. Catalpa leaves occasionally have several pointed lobes, but this feature is more common in Catalpa’s Asian relative, Paulownia (Paulownia tomentosa, Empress Tree). The leaves are otherwise entire (lacking teeth). 

Most leaves are arranged in either an alternate or opposite configuration, but Catalpa leaves are usually neither, they are whorled. Whorled leaves are attached in groups of three or more, and in the case of Catalpa, three. Because both Catalpa and Paulownia leaves can have several pointed lobes, it’s usually easier to distinguish them by looking for whorled versus opposite leaf attachment, indicating Catalpa versus Paulownia. But Catalpa occasionally has opposite leaves. 

So, if Catalpa and Paulownia can both sometimes have pointed or unpointed leaves, and Catalpa leaves aren’t necessarily always whorled, how can we tell them apart? Remember that fruits and flowers are more important to tree classification than leaf shape. Catalpa speciosa has a trumpet-shaped white flower with yellow and purple markings. Paulownia tomentosa flowers are similarly shaped, but lavender in color. The seed pods differ as well. Catalpa seeds are contained in slender pods that resemble huge green beans and range from 12 inches to 24 inches in length. Paulownia seeds are contained in compact pods that resemble giant pistachios. 

Chinese Catalpa (Catalpa ovata) is actually more similar to Northern Catalpa than Paulownia, but less common in my experience. Chinese Catalpa, like Northern Catalpa, usually has whorled leaves in groups of three, and it has long, slender seed pods, but Chinese Catalpa’s pods are far more slender and, in my limited experience, are more prone to hanging together in dense clumps. The flowers are also more yellow than Northern Catalpa’s, hence another common name, Yellow Catalpa. 

Northern Catalpa bark is deeply furrowed and brownish-gray on mature Catalpa trees of either variety. 

Mature Catalpas typically have a height of 50 to 80 feet and a trunk diameter of approximately 2. 5 feet. Ohio’s Champion Northern Catalpa, located in Lawrence County, has a height of 71 feet, a trunk diameter of 7.3 feet, and a crown width of 71 feet. Catalpas typically have spreading, craggy crowns, and often, crooked trunks. The trees are fast-growing, but have a short life span, typically around 60 years. 

As discussed above, Northern Catalpa leaves can be very similar to Paulownia, but Catalpa can be distinguished by its leaves or leaves scars in groups of three, its long seed pods, and its white flowers. Southern Catalpa (Catalpa bignonioides) is even more similar, but it has smaller seed pods, smaller, more abundant flowers, and leaves that emit a foul odor when crushed. Southern Catalpa is native to several southern states, and is seldom seen in Ohio. 

ID Summary: Unusually large heart-shaped leaves in groups of three. Slender foot-long or longer cylindrical seed pods. White trumpet-like flowers. 

Catalpa is occasionally seen in wooded areas, but is mostly cultivated. Northern Catalpa is native to a small area near the confluence of the Mississippi and Ohio Rivers, but it’s widely planted in the Eastern U.S. Archeological evidence suggests that it might have once been much more widespread, growing as far east as West Virginia. Its similarity to Southern Catalpa also suggests that their ranges were once contiguous or overlapping. The Columbus Street Tree Inventory regards Catalpa as an Ohio native and recommends planting it, as it represents only 0.35% of the city’s trees, and would provide greater species diversity. 

Catalpa lumber (Northern and Southern, undifferentiated) has a Janka hardness of 550 lbf and a density of 0.46 g/cc, according to the Wood Database, compared to the median of my list of 73 Ohio trees of 1,075 lbf and 0.64 g/cc. Catalpa is not widely used as lumber, but it has good rot resistance and was once often planted and used for fence posts. Catalpa has an attractive golden color and is sometimes used for carvings and cabinetry. Catalpa has a rather coarse texture, but it nails, stains, and finishes well, and has an unusually low degree of differential shrinkage and warpage. The Wood Database regards it as an underrated lumber species, neglected in part due to its scattered distribution. 

The Any One Wood website lists the following virtues for Catalpa: 

• It is useful for furniture, cabinetry, musical instruments, carvings, and veneers,
• It is termite resistant,
• It is a sustainable source of wood, and
• It takes a good finish and is easy to work with. 

They also note that “Northern Catalpa is not known to have any spiritual properties associated with it”. For whatever reason, there appears to be little information on the folkloric aspects of Catalpa.  

Because of its rapid growth, the deep shade it produces, and its tolerance for a variety of conditions, one of Catalpa’s chief uses today is for landscaping. However, the large leaves and seed pods are messy, and Catalpa’s lack of fall color limit its popularity. But rapid growth and tolerance of various soil and moisture conditions make it useful for land reclamation. 

No part of the Catalpa tree is edible to humans, but its leaves are eaten by the Catalpa Sphinx Moth (Ceratomia catalpae). Catalpa worms are one of the favorite baits for fishing, and many Catalpa trees have been planted solely for the production of worms. 

According to the USDA Plants Database, “Pioneer doctors used the seed pods and seeds to make a decoction for chronic bronchial affections, spasmodic asthma, labored breathing and heart problems. The juice from either the leaves or roots was used to treat swelling of an eye or cutaneous affections. Green leaves were crushed and placed on swollen lymph glands. The bark was dried then ground to a powder and taken, or brewed in a tea and taken for swollen lymph glands”. 

I found no information on Native uses for Catalpa in the Native American Ethnobotany Database. However, various sources listed the following applications: 

• Bark and seeds boiled in water to make eyewash,
• Bark and seeds made into a tea for treating malaria, asthma, whooping cough, and cardiac problems,
• Seeds and pods boiled to make a wash for flushing wounds.

Northern Catalpa prefers alkaline, moist, but well-drained fertile soil, and full to partial sun. But as mentioned above, Catalpa tolerates less-than-ideal conditions, and can become invasive. 

Environmentally, birds and mammals make little use of Catalpa seeds, but Catalpa Sphinx (Ceratomia catalpae) and Tersa Sphinx caterpillars (Xylophanes tersa) feast on the leaves. In fact, several accounts relate that caterpillars are known to entirely defoliate Catalpas, without killing the trees. Bees are attracted to Catalpa flowers, which are sometimes a significant source of honey. 

Northern Catalpa doesn’t get the respect that a number of other trees do, but its huge leaves in summer, and striking, conspicuous seed pods in winter make it an interesting and highly recognizable addition to the landscape.  

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You can also listen to my talks on Ohio Broadleaf Tree Identification on YouTube, Part 1 and Part 2.