Sometimes I fall in love with a plant for its name. Prairie smoke, rattlesnake master, spiderwort, juneberry, ninebark: how can someone not covet these? On the other hand, you’ve got plants with names like American hornbeam. Not a snappy handle. But blue beech is, and so is musclewood—and they’re all three common names for the same tree: Carpinus caroliniana. And this small, shade-happy native has more to recommend it than a name. Its smooth, blue-gray trunk has vertical fluting that looks like muscles, and it carries male and female flowers (catkins) in early spring and winged nutlets in fall and winter. Fall color is a dramatic coat ranging from yellow to purple-red. What’s in a name? Plenty—and then some.
Common name: American hornbeam, blue beech, water beech, musclewood, ironwood
Botanical name: Carpinus caroliniana
Plant type: Deciduous large shrub or small tree
Zones: 3 to 9
Height: 20 to 30 feet tall and wide
• Sun: Best in part to full shade
• Soil: Rich, humusy, acidic
• Moisture: Average to moist
• Mulch: Mulch to help keep soil moist.
• Pruning: If left alone, C. caroliniana will sucker and form a multistemmed shrub. Can easily be pruned to a single trunk, and maintained as a small tree. Can also be pruned to form a hedge or screen.
• Fertilizer: None needed.
• By seed or cuttings.
Pests and diseases
• Two-lined chestnut borer may attack stressed trees.
• May be vulnerable to canker, leaf spots, fungi, powdery mildew, and wood rot.
• In the wild, Carpinus caroliniana grows as an understory tree. Withstands periodic floods.
• C. caroliniana is a slow grower, averaging about 8 to 10 feet in 10 years.
• Because of its small size and ability to handle shade, C. caroliniana is a good tree for small urban lots.
• It’s also great to use as a transition between a garden and a forest, or in a woodland setting.
• Birds feed on the nutlets that form in the fall.
The two cultivars (‘Palisade’ and ‘Pyramidalis’) are all but unavailable. Look for the species.
All in the family
• The leaves of C. caroliniana resemble beech leaves (hence blue beech and water beech as common names), but it is not a beech (Fagus spp.). Other trees in the Carpinus genus include European hornbeam (C. betulus), heartleaf hornbeam (C. cordata), and Japanese hornbeam (C. japonica).
• Other trees in the birch family include birches, alders, hazels, and hop hornbeams.
(Text by Elizabeth Noll, photo courtesy of the Kemper Center for Home Gardening at the Missouri Botanical Garden.)