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Northern Catalpa - Tree Information Sheet
Uses of Northern Catalpa: Landscaping, Medicinal, Culinary, etc...
Northern catalpa is primarily used today as a large ornamental shade tree. It is widely planted in urban areas as a street and lawn tree. Conservation uses include being planted in mined-land reclamation projects and shelterbelts.
General Characteristics
Required Growing Conditions
Trumpet-creeper Family (Bignoniaceae). It is a perennial deciduous tree which readily grows in USDA Hardiness Zones 4 to 8. The height at 20 years is about 20 feet. Catalpas prefer moist, deep, well drained soil, but adapts to dry or wet soils. The soil pH may range from 5.5 to 7.0. It prefers an open sunny space to partial shade. It is tall with an irregular, open-rounded to narrow-oval crown. This tree comes into leaf very late in the spring and it is one of the first to lose its leaves in the fall. Its longevity is about 60 years.
The tree bark ranges from scaly to ridged, to blocky plates. On young tree seedlings the bark is thin and easily damaged by impact, or rodents.
Twigs in winter have a unique identifying characteristic. They have sunken leaf scars which resemble suction cups. Their whorled arrangement of 3 scars per node is another trait easily identified.
Leaves are simple, large ovate to ovate-oblong, from 8 to 12 inches long, are heart-shaped tropical looking without any lobes and are yellowish green in color. Leaves are generally opposite on large branches and often whorled in 3 on young stems. They turn an undistinguished yellow in the fall before dropping.
The flowers of catalpa are perfect. Flowering takes place in late spring to early summer. They occur as large clusters of showy, white, bell-shaped corollas of 5 lobes with ruffled edges and yellow, orange or purple interior spotting or streaking. Individual flowers are showy, tubular up to ½ inch broad. They are branched in about 10 inch clusters at the stem tips.
Seedpods are slender and green in the summer growing from 10 to 24 inches long, looking similar to an exaggerated green bean. They mature in the fall, turn dark brown, split open lengthwise to let seeds fall in the spring. The shape and color of the mature seedpod gives rise to the common name of cigar tree. It has been extensively propagated for over 200 years. It can now be found in most states east of the Rocky Mountains and in Utah.
Cultivation and Care
When placed as an ornamental in a yard setting care must be taken to ensure it is not too close to a building, fence, property line or septic system. Ample space should be provided to let it reach a mature height.
Status
Weediness This plant may become weedy or invasive in some regions or habitats and may displace desirable vegetation if not properly managed.
General Upkeep and Control
The biggest management problem with a catalpa tree used as an ornamental is litter. It will drop a heavy load of flowers in the spring, then a plentiful supply of leaves in the fall and finally a lot of large seedpods in the winter.
Pests and Potential Problems Larva of the catalpa sphinx caterpillar (Ceratomia catalpae) eats leaves. Almost complete defoliation may occur in some years.
Immature seeds in the pods are often destroyed by a small yellow grub, the larva of a gnat.
Brown leaf spots on leaves are often created by the fungi Macrosporium catalpae. Catalpa is also susceptible to the decay fungus Polystictus versicolor. Powdery mildew causes a white powdery coating on the leaves. When severe the leaves turn yellow and drop. Verticillum wilt will make the branches die, and can eventually kill trees. Catalpa midge (Cecidomyia catalpae Comstock) causes leaf spots, injures terminal buds and branch tips, as well as seeds in the pods.
Environmental Concerns It is an invasive, weedy tree which escapes cultivation easily. The flowers, long seedpods and seeds fall down from spring through winter, and create a mess on the ground anywhere near the tree.
Cultivars, Improved, and Selected Materials (and area of origin) There are two species of catalpa native to North America, northern catalpa (Catalpa speciosa) and southern catalpa (Catalpa bignonioides). They appear very similar but are two distinct species. One variety of C. speciosa has been documented: pulverulenta from Paul & Son.
Control Please contact your local agricultural extension specialist or county weed specialist to learn what works best in your area and how to use it safely. Always read label and safety instructions for each control method. Trade names and control measures appear in this document only to provide specific information. USDA, NRCS does not guarantee or warranty the products and control methods named, and other products may be equally effective.
Source: USDA, NRCS, PLANTS Database, plants.usda.gov.
National Plant Data Center, Baton Rouge, LA 70874-4490 USA
