2018-11-30 / Home & Garden

American Hornbeam— Tree with Muscle

Stopping to smell the flowers
By Arlene Marturano

South Carolina’s Arbor Day is the first Friday in December, the start of tree planting season for the climate. Since urban sprawl has reduced the tree canopy across the Midlands, residents can reverse deforestation by planting trees yearly from Arbor Day through February.

One of the finest native deciduous hardwood trees to add to the understory layer of residential or commercial property is the birch family member American hornbeam, Carpinus caroliniana, aka as ironwood, blue beech, and musclewood. The common name ironwood refers to the extremely dense wood once used by Native American Chippewa to support tents and wigwams and pioneers to make machinery gears, ox-yokes, beams, mallets, levers, bowls, dishes, hockey sticks, and golf clubs. Today the wood is used for piano parts, carving boards and tool handles.

The tree’s dappled blue-grey bark and translucent chartreuse spring serrated foliage resemble beech trees, hence the moniker blue-beech. Musclewood describes the fluted trunk and branches which look like flexed sinewy muscles.


The hornbeam offers a kaleidoscope of leaf color in fall. The hornbeam offers a kaleidoscope of leaf color in fall. American hornbeam’s extensive eastern range from southern Canada to Florida and Texas reveals its climate adaptability to USDA zones 3-9.

Landscape consultant and photographer Rick Darke praises hornbeam as one of the best small graceful ornamental understory shade trees for all seasons. In spring, green male and white female catkins appear prior to translucent leaves. Dangling hop-like fruits called nutlets accompany emerald summer foliage. Autumn leaf color is a kaleidoscope of gold, orange, crimson and purple. In winter the fluted blue-grey trunk and horizontal branching captures attention.

Slow growing at a foot per year, hornbeams are very shade tolerant under a deciduous canopy. To attain a mature height of 20-30’ they prefer deep, organically rich, moist, slightly acidic soil. Hornbeam tolerates wet sites but adapts to dry. The largest local hornbeam resides in Congaree National Park at 65’ tall and a spread of 45’. Except for leaf spot, twig blight, and cankers, hornbeam is considered pest and disease free.


Musclewood describes the fluted trunk and branches which look like flexed sinewy muscles. Musclewood describes the fluted trunk and branches which look like flexed sinewy muscles. Municipalities site hornbeams in parks and as street trees for their compact stature, strong branches requiring little pruning or repair, and longevity (150 years).

Homeowners plant the tree in partial to full shade as a specimen, shade tree in small yards or garden rooms, or privacy screen. Carpinus allée line some public garden pathways. Children, attracted to the low hanging strong branches and closed canopy find hornbeam ideal as a climbing, hiding, and fortress tree.

Female catkins give way to dangling hop-like fruit called nutlets consumed by wildlife.Female catkins give way to dangling hop-like fruit called nutlets consumed by wildlife.
Hornbeams provide cool protective shade for wildlife. Birds like ruby-throated hummingbirds nest in the erect forks and dense crown. Finches, cardinals, mockingbirds, grosbeaks, bobwhite, wild turkey, ruffed grouse, and grey squirrels consume the nutlets. Rabbits, fox, beaver, and deer feed on twigs and leaves. Beavers use the tree extensively because it often grows around streams and rivers.

Hornbeams are caterpillar host plants to 68 species of moths and butterflies including eastern tiger swallowtail, striped hairstreak, and red-spotted purple. Caterpillars are primary food for nestlings.

Although hornbeams were introduced into cultivation in the early 1800s, they are often overlooked today. While the species is worthy of a place in your garden, cultivars include ‘Firespire’, ‘Native Flame’, and ‘Palisade’. Garden centers like Woodley’s and Cooper’s can special order the tough native tree with muscle.

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