Developing seed clusters on native tree American hornbeam.

Maturing seed clusters on American hornbeam. Photo: Miri Talabac

Updated: July 12, 2022

About American hornbeam

Carpinus caroliniana
Deciduous tree
Birch family (Betulaceae)

Maryland Distribution: throughout the state; woodland understory and woods-edge habitat
Height: 20 to 30 feet tall
Flowers: yellow-green to beige-yellow hanging catkins; between late March and early May; wind-pollinated
Fall color: variable, ranging from yellow to orange-red or purplish-red
Sun: part sun to shade, though tolerant of more sun
Soil: moist to periodically wet; pH adaptable (acidic to slightly alkaline)

Garden Uses: This small to medium-sized deciduous tree is a great candidate for landscapes with shade from canopy trees or buildings and less-than-perfect drainage. An adaptable species, it withstands occasional mild flooding and can also tolerate drier sites. Trunks on wild trees can develop a lean with age, usually towards available light when growing in darker areas, and are often multi-stemmed and low-branched. Cultivated trees can develop a more even, symmetrical canopy and their lowest branches can be gradually removed to better define the trunk.

Blooms emerge before the foliage finishes expanding, adorning the branches like dangling ornaments. Emerging young leaves may be blushed reddish-bronze or purplish-red. Winged green seed clusters, loosely resembling a cluster of hops, pale as they mature and turn tan and dry by autumn. Seeds are dispersed by both birds and wind, and clusters may persist into winter.

American hornbeam tolerates trimming fairly well, though any desired pruning should be limited to winter, when possible, to avoid a lot of sap “bleeding.”

Alternate common names for this species are: musclewood, for the flexed-muscle texture of mature trunks; ironwood, for the hard, dense, heavy wood; blue beech, for the beech-like appearance of the foliage and bluish-gray bark; and water beech, for its adaptability to floodplains. Despite these names, hornbeam is not related to beech.

Few cultivars exist for this species, with most selected for enhanced leaf color in new growth and/or autumn.

Wildlife: Songbirds feed on buds, catkins, and mature seeds; fallen seeds support ground-feeding birds like Ruffed Grouse, Northern Bobwhite, Wild Turkey, and Wood Duck. Squirrels also consume the seeds.

American hornbeam foliage hosts Eastern Tiger Swallowtail and Striped Hairstreak butterflies, plus several species of moths.

Blooms of native tree American hornbeam.
Catkin blooms in spring. Photo: Miri Talabac
Bronze-tinged young foliage on American hornbeam.
Young foliage can have a reddish or bronzy blush. Photo: Miri Talabac
Autumn leaf colors on American hornbeam.
Red-orange and yellow autumn colors in a woodland populated by hornbeams. Photo: Miri Talabac

 

Trunks develop a muscular texture as they mature.

Photo: Miri Talabac

Growth habit of American hornbeam maintained in a garden setting.

Photo: Miri Talabac

Growth habit of American hornbeam maintained in a garden setting.

Photo: Miri Talabac

Additional resources

American Hornbeam | Maryland Biodiversity Project gallery and distribution map

American Hornbeam | U.S. Forest Service

Compiled by: Miri Talabac, Horticulturist & Coordinator, Home & Garden Information Center. 2022

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