top of page

American Hornbeam

Carpinus caroliniana, the American hornbeam, is a small hardwood tree in the genus Carpinus. American hornbeam is also known as blue-beech, ironwood, musclewood and muscle beech. It is native to eastern North America, from Minnesota and southern Ontario east to Maine, and south to eastern Texas and northern Florida. It also grows in Canada (southwest Quebec and southeast Ontario). It occurs naturally in shaded areas with moist soil, particularly near the banks of streams or rivers, and is often a natural constituent understory species of the riverine and maritime forests of eastern temperate North America.



American hornbeam is a small tree and often has a fluted and crooked trunk. The bark is smooth and greenish-grey, becoming shallowly fissured in all old trees. Flowers are green catkins and bloom from April until June. Monoecious. Male flowers are 1 to 1½ inches long; female flowers are 2 to 3 inches long with three-lobed bracts. Fruit is a 1/3-inch winged nutlet attached to three-lobed bracts. The seeds often do not germinate till the spring of the second year after maturating. Leaves are simple, alternate, 2 to 5 inches long. Spring foliage changes from crimson to green, then becomes deep green in summer. Fall foliage ranges from yellow to a scarlet tinge.


Table of Contents


Height(Avg)

20 - 40 feet


Width-Circumference (Avg)

20 - 35 feet


Approximate pH

4.0 - 7.4


Types of American Hornbeam


The American hornbeam has some cultivars with slightly different appearances. They include:

  • Carpinus caroliniana 'J.N. Upright': Known as Firespire, this cultivar features brilliant red-orange fall color and grows to around 20 feet tall and 10 feet wide.

  • Carpinus caroliniana 'JFS-KW6': This cultivar gets its name, Native Flame, from its bright red fall color. It can reach around 30 feet high and 20 feet wide.

  • Carpinus caroliniana 'CCSQU': This cultivar sports yellow-orange fall color. It has an oval shape, reaching around 20 to 30 feet tall and 15 to 20 feet wide.


Planting American Hornbeam


American hornbeam typically comes from nurseries as a single-stem tree. Most cultivars of American hornbeam are columnar in shape when they are young, then develop a pyramidal shape as they age. Plant narrow, upright trees in groups to create a living screen or windbreak. Or use this tree as a specimen plant in a narrow yard or in a curbside planting strip. (A low grower, it can take decades to reach full height—so plan accordingly).


American Hornbeam Care


The American hornbeam looks gorgeous in all seasons. Many gardeners like to use a hornbeam as the focal point in a perennial garden by surrounding it with complementary flowers and mulch. That way, it won't outcompete other trees. Along those lines, remember to consider its mature size when planting. While it's a slow grower (it can take decades to reach its maximum size), this tree might cause crowding problems for neighboring trees down the road. And the tree can be difficult to transplant due to its expansive root system, so you'll want to pick an ideal spot from the start.


For best results, start your American hornbeam from seed on site, or select a young tree from a reputable nursery. This species is highly adaptable and can withstand some flooding, but it has a hard time dealing with drought conditions. Other than providing regular watering, the hornbeam is relatively low-maintenance.


Light


The American hornbeam is commonly found within the understory of hardwood forests, so it can thrive in partial to full shade. It is also quite adaptable and can tolerate full sun. Ideally it should get around four to six hours of light per day.


Soil


Hornbeams prefer fertile, moist, well-draining soil with an acidic to neutral soil pH, though they can tolerate slight alkalinity. While they are able to grow in clay soil, loam is best. Poor soil drainage will cause them to grow more slowly.


Water


This tree needs regular watering during dry spells. Installing drip irrigation for summer maintenance is helpful. When the weather is hot and dry, give the tree a deep soak once per week. A layer of mulch over the roots will help to retain soil moisture. To establish the roots of a new tree, keep the ground damp for the first two to three years during the growing season.


Temperature and Humidity


Hornbeams grow in a wide range of climates, from Canada to Florida, so they are tolerant of broad temperature differences and seasonal conditions. However, the species is less common in dry climates; at least moderate humidity is preferred for optimal growth.


Fertilizer


American hornbeams typically do not need fertilizer. If there is turf grass around your tree, the tree may need fertilizer; turf grass has shallower roots and out-competes the tree for nitrogen.


Pruning


This tree can form multiple trunks if left to its own devices. So if you'd like your hornbeam to have a single trunk with foliage growing above, make sure to prune it to have only one central leader. Other than that, you generally only have to prune to remove dead or diseased branches.


You can also prune this species to create a formal hedge or living fence. This works well for adding privacy to your yard without the eyesore of a tall fence. Regular pruning will be necessary to maintain the hedge shape.


Pests and Plant Diseases


The American hornbeam is extremely resistant to both pests and diseases, so problems rarely arise. However, hornbeam trees can develop cankers, or dead sections on the bark or branches. And they can present with leaf scorch or leaf spots. Proper maintenance and appropriate water amounts should prevent this. Insects that can affect a hornbeam include maple mealybugs and two-lined chestnut borers. So if you notice damaged foliage, they might be the culprits.


Uses

  • The wood has been used for tool handles, mallet heads, levers and other small wooden objects.

  • American pioneers used it for bowls and dishes, as it is not subject to cracking.

17 views0 comments

Recent Posts

See All
bottom of page