American Hornbeam
Carpinus caroliniana

Family: Betulaceae (beh-tyoo-LAY-see-ee) (Info)
Genus: Carpinus (kar-PINE-us) (Info)
Species: caroliniana (kair-oh-lin-ee-AN-uh) (Info)

Category:

Trees

Height:

20-30 ft. (6-9 m)

Spacing:

20-30 ft. (6-9 m)

Hardiness:

USDA Zone 3a: to -39.9 C (-40 F)

USDA Zone 3b: to -37.2 C (-35 F)

USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Partial to Full Shade

Danger:

N/A

Bloom Color:

Green

White/Near White

Bloom Time:

Mid Spring

Late Spring/Early Summer

Foliage:

Deciduous

Other details:

Average Water Needs; Water regularly; do not overwater

Soil pH requirements:

4.6 to 5.0 (highly acidic)

5.1 to 5.5 (strongly acidic)

5.6 to 6.0 (acidic)

Patent Information:

Non-patented

Propagation Methods:

From semi-hardwood cuttings

From seed; direct sow outdoors in fall

From seed; winter sow in vented containers, coldframe or unheated greenhouse

From seed; stratify if sowing indoors

Seed Collecting:

Allow unblemished fruit to ripen; clean and dry seeds

Properly cleaned, seed can be successfully stored

Regional

This plant has been said to grow in the following regions:

Bartow, Florida

Ottawa, Illinois

Wheaton, Illinois

Benton, Kentucky

Isle, Minnesota

Piedmont, Missouri

Frenchtown, New Jersey

Bolivar, New York

Kinston, North Carolina

Summerfield, North Carolina

Cincinnati, Ohio

Birdsboro, Pennsylvania

Glenmoore, Pennsylvania

North Augusta, South Carolina

Dickson, Tennessee

Conroe, Texas

New Caney, Texas

Kenosha, Wisconsin

show all

Gardeners' Notes:

3
positives
3
neutrals
0
negatives
RatingContent
Positive

On Dec 28, 2013, Rickwebb from Downingtown, PA wrote:

A handsome understory forest tree that I see in mature, climax forest areas of southeastern Pennsylvania; and I've seen it in the shady canyons of Starved Rock State Park near Ottawa, Illinois. It makes a fine small or medium sized ornamental tree for landscapes, but the soil must be good quality and not dry out too much. Because it is slow growing, about 8 to 12"/yr, and because it develops coarse lateral roots and is sort of hard to transplant, only big nurseries or native plant nurseries grow it. Handsome birch-like foliage turns yellow or even orange or red with more sun. It has handsome beech-like bark that is smooth and gray.

Positive

On Aug 16, 2011, miscanthus65 from Summerfield, NC wrote:

Beautiful tree! These grow around a creek in my woods...other trees in the area are beech, frasier magnolia, maple, oak and sourwood.

Positive

On May 9, 2004, Farmerdill from Augusta, GA (Zone 8a) wrote:

This tree also grows in Virginia frequently in the same terrain as beech. The old folks also called it iron wood. In those those day we split fence posts out of chestnut oak. This was done with a maul and wedge. Because they were expensive most folks only used two steel wedges. Wooden wedges call "gluts" were cut from iron wood (hornbeam) to hold an opening so the steel wedge could be moved to a new position. Also made great firewood.

Neutral

On May 9, 2004, MotherNature4 from Bartow, FL (Zone 9a) wrote:

Because of the unusually hard wood, this tree is known throughout Florida as "Ironwood."
The smooth bark and fluted trunk resemble muscles, thus the nickname "muscle tree."

Neutral

On Apr 24, 2004, Hornbeam from Chincoteague Island, VA wrote:

cultural notes: soak seeds in warm water and let stand in water for 24 hours. Warm stratify 60 days, cold stratify for 90 days. Sow seed 1/8" deep, tamp down the soil and mulch.

Note: Sporadic germination may occur over a 2-3 year period.

Neutral

On Aug 31, 2001, smiln32 from Oklahoma City, OK (Zone 7a) wrote:

American hornbeam is a slow-growing, deciduous, small to medium-sized understory tree with an attractive globular form. It is native to Missouri where it is typically found in rich moist woods, valleys, ravine bottoms and rocky slopes along streams throughout the eastern and Ozark regions of the State (Steyermark). Typically grows 20-35' tall. The smooth, gray trunk and larger branches of a mature tree exhibit a distinctive muscle-like fluting that has given rise to another common name of musclewood for this tree. Flowers appear in spring in separate male and female catkins, with the female catkins giving way to distinctive clusters of winged nutlets. Serrated, elliptic-oval, dark green leaves often produce respectable shades of yellow, orange and red in fall.

The extremely... read more