American hornbeam | Carpinus caroliniana

The American hornbeam is a native forest understory tree in the Chicago area, making it useful for shady landscapes and naturalized or woodland gardens. New leaves emerge reddish-purple, changing to dark green, then turn yellow to orange-red in the fall, offering a kaleidoscope of color throughout the year. Even in winter, the tree’s fluted blue-gray bark with long, sinewy ridges make it a special addition to the landscape.

This species is native to the Chicago region according to Swink and Wilhelm’s Plants of the Chicago Region, with updates made according to current research.

Family (English) Birch
Family (botanic) Betulaceae
Planting site Residential and parks
Tree or plant type Tree
Foliage Deciduous (seasonally loses leaves)
Native locale Chicago area, Illinois, North America
Size range Small tree (15-25 feet), Medium tree (25-40 feet)
Mature height 20-30 feet
Mature width 20-30 feet
Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily), Full shade (4 hrs or less of light daily)
Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8, Zone 9
Soil preference Acid soil, Moist, well-drained soil, Wet soil
Tolerances Alkaline soil, clay soil, Dry sites, Wet sites
Season of interest early winter, midwinter, late winter, late summer, early fall, mid fall
Flower color and fragrance Inconspicuous
Shape or form Multi-stemmed, Round
Growth rate Slow
Transplants well No
Wildlife Game birds, Small mammals, Songbirds
Has cultivars Yes

More Information

Native Geographic Location and Habitat

C-Value: 8. American hornbeam is native to the eastern half of the United States. It is commonly found in wooded areas as an understory tree.

Bark Description

The blue-gray bark is fluted with long, sinewy ridges.

Leaf Description

Simple, alternate leaves are 2 1/2 to 5 inches long, with double serrated margins and pointed tips. Leaves emerge reddish-purple, changing to dark green, then yellow to orange-red in the fall.

Flower Description

Flowers are inconspicuous. Small female flowers bloom near the ends of the twigs and tiny male flowers in pendulous catkins appear in April.

Fruit and Nut Description

Light brown nutlets mature in October and have a three-lobed bract appearing as an umbrella over the nuts. Nutlets and bracts are borne in dangling clusters. Bracts change from light green to yellow in fall.

Cultivars

These plants are cultivars of a species that is native to the Chicago Region according to Swink and Wilhelm’s Plants of the Chicago Region, with updates made according to current research. Cultivars are plants produced in cultivation by selective breeding or via vegetative propagation from wild plants identified to have desirable traits.

Firespire™ American hornbeam (Carpinus caroliniana ‘J.N. Upright’):

A narrow, upright cultivar with improved red-orange fall color, this tree matures to 20 feet high by 10 feet wide.

J.N. Strain American hornbeam (Carpinus caroliniana ‘J.N. Strain’):

A vigorous cultivar with improved orange-red fall color.

Native Flame® American hornbeam (Carpinus caroliniana ‘JFS-KW6’):

An upright form with bright red fall color; 30 feet high by 20 feet wide.

Palisade® American hornbeam (Carpinus caroliniana ‘CCSQU’):

An upright oval form with yellow-orange fall color; 20 to 30 feet high by 15 to 20 feet wide.