American hornbeam (Carpinus caroliniana): what the agencies record

This page reports what US federal publications say about one tree. It does not identify trees from descriptions or photos and does not say what should be done with any tree. The family overview, tree species in the agency records, explains the sources and holds the comparison table. The European tree of the same genus has its own page, hornbeam, and a second native small tree is covered at eastern hophornbeam.

At a glance

Native range and climate

The Silvics of North America handbook (Agriculture Handbook 654, Volume 2, 1990) calls American hornbeam a small, slow-growing, short-lived tree of the understory in eastern mixed hardwood forests. It is native to most of the eastern United States and reaches southwest Quebec and southeast Ontario. The western limit lies just beyond the Mississippi River, from north-central Minnesota to the Missouri River, running southwest through much of the Ozark and Ouachita Mountains into eastern Texas. The handbook says it is absent from the Mississippi River bottomland south of Missouri, the lowermost Gulf Coastal Plain, the southern two-thirds of Florida, the New Jersey pine barrens, much of Long Island, Cape Cod, northern and eastern Maine, and the White and Adirondack Mountains. Outside the United States it is found in central and southern Mexico, Guatemala and western Honduras.

Silvics gives mean annual precipitation from 710 mm (28 in) in Minnesota to 1,570 mm (62 in) along the Gulf Coast, mean January temperatures from minus 13 to 16 degrees C (8 to 60 degrees F), and frost-free periods from 80 to 320 days. It says the upper elevation limit is 910 m (3,000 ft) in the Great Smoky Mountains.

Sites and forest cover

The handbook says best growth is on rich, wet-mesic sites with abundant soil moisture but enough drainage to avoid saturation: alluvial or colluvial soils in the transition between mesic and wet areas, such as near lakes and swamps, on well-drained river terraces, in coves and ravine bottoms. Soil pH is normally acidic, from 4.0 to 5.6, and as high as 7.4. The species is only moderately tolerant of flooding and is eliminated from sites inundated more than 25 percent of the time, so it is absent or rare on the wettest sites. It also grows, to a lesser extent, on mesic to xeric sites. American hornbeam is typically an understory species and only rarely occurs in the overstory or dominates a stand; Silvics lists it in forest cover types including Beech-Sugar Maple, White Oak-Black Oak-Northern Red Oak, River Birch-Sycamore and Pin Oak-Sweetgum.

Catkins and nutlets

The species is monoecious, with male and female catkins on the same tree appearing in spring as the leaves open. The handbook gives male catkins as pendant and 3 to 4 cm (1.25 to 1.5 in) long, and female catkins as 13 to 19 mm (0.5 to 0.75 in) long. Flowering occurs between March 20 and May 6 in the Southeast and in April through May in the North. The fruit is an ovoid, ribbed nutlet 5 to 8 mm (0.2 to 0.3 in) long, borne at the base of a three-lobed involucre, and it matures in one season. Large seed crops come at intervals of 3 to 5 years. Birds are the main dispersers, with wind carrying seed short distances. The handbook says germination capacity of stratified seed is low, usually under 60 percent and occasionally as low as 1 to 5 percent.

Size, shade and growth

Silvics says American hornbeam is unsuited for commercial timber production because it is usually small, twisted and multi-stemmed: in undisturbed stands 70 to 93 percent of the trees were saplings under 13 cm (5 in) in diameter, and under 1 percent were 25 cm (10 in) or larger. It calls the species very shade tolerant, capable of persisting in the understories of late seral and climax communities, with tolerance greatest in seedlings and declining with age, so that an opening in the canopy is needed for the tree to reach maturity. On certain southern sites the handbook says it is so aggressive that it replaces overstory species lost through logging or catastrophe.

Wood

The handbook describes the wood as close-grained, very hard and heavy, but says it is little used because such a small tree is rarely converted into sawed products; it names tool handles, levers, wedges and mallets as uses. The Wood Handbook (FPL-GTR-282, 2021) has no strength row for American hornbeam in Table 5-3b. The NRS-38 weight table does list it:

The green weight is the figure used in the log weight calculator.

Damaging agents the handbook names

Silvics says insect and disease damage is not a serious problem with American hornbeam. The species is resistant to frost, with succulent foliage able to withstand minus 8.5 degrees C (17 degrees F), and the handbook calls the tree very windfirm. It is susceptible to fire: wildfires severe enough to kill the hardwood component of white oak stands in Rhode Island eliminated it. The handbook also says forested campground recreational use disposes the tree to increased disease, insect infestation and decline, and ranks it the tree least able to withstand such use among 22 hardwood species evaluated. White-tailed deer browse the reproduction but do not prefer it, and beaver use it heavily where it is readily available.

For who takes reports of regulated pests, see reporting a pest in the United States, and pests and diseases by country sets out which ones agencies regulate.

Sources

• USDA Forest Service, Silvics of North America, Volume 2 Hardwoods (Agriculture Handbook 654, Burns and Honkala, 1990), Carpinus caroliniana chapter by Metzger, read October 9, 2026
• USDA Forest Service, Forest Products Laboratory, Wood Handbook (FPL-GTR-282), 2021, Table 5-3b (no row for this species), read October 9, 2026
• USDA Forest Service, Northern Research Station, Research Note NRS-38, Miles and Smith, 2009, Table 1A, read October 9, 2026
• USDA Natural Resources Conservation Service, PLANTS Database, profile data for Carpinus caroliniana (symbol CACA18), read October 9, 2026