River birch (Betula nigra): 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.

At a glance

Item	What the source records
Scientific name	Betula nigra L. in USDA PLANTS, birch family
Other names	Red birch, water birch and black birch (Silvics)
Native status, USDA PLANTS	Native in the lower 48 states
Size, Silvics	Average merchantable size is 15.2 to 24.4 m (50 to 80 ft) tall and 61 to 91 cm (24 to 36 in) in diameter at breast height; in the lower Mississippi River Valley isolated trees attain heights of 30.5 m (100 ft) and diameters of 150 cm (60 in)
Form, Silvics	The clear bole is relatively short, with several ascending major branches from 4.6 to 6.1 m (15 to 20 ft) above the ground; multiple stems, probably from stump sprouts, are common
Green weight of the wood, NRS-38	57 lb per cubic foot, without bark

Native range

The Silvics of North America handbook (Agriculture Handbook 654, volume 2, 1990) says the primary range of river birch is the southeastern quarter of the United States, from eastern Texas and southeastern Iowa to Virginia and northern Florida. Scattered populations are found along rivers and streams as far north as southern Minnesota, central Wisconsin and the middle New England States, and the northern limit in the Great Lakes region corresponds to the boundary of the terminal moraine of the Wisconsin glacier. The handbook names major exclusions within the primary range: the southern half of the Mississippi River flood plain, the lower coastal plain, the Appalachian Mountains, and limestone areas of southern Missouri, central Tennessee and central Kentucky. In western North Carolina it is found primarily below 550 m (1,800 ft) elevation. Silvics calls it the only birch whose range includes the southeastern coastal plain.

Flowers and seed

Silvics says river birch is monoecious, with male catkins formed at twig tips in fall and maturing in April or May of the following year, and seed-producing female catkins borne on spur-shoots that appear with the leaves. The fruit matures in late spring or early summer, which the handbook says makes it the only birch that does not produce seed in fall, and good seed crops occur almost every year. The handbook adds that pollen production is abundant and that birch pollen is a heavy contributor to the hay fever problem.

Growth, bark and uses

The handbook says information on growth and yield is scarce because most commercial use comes from natural stands, where river birch wood is combined with that of other birches, beech and maples. In Ohio plantations, 58-year-old river birches average 23 to 41 cm (9 to 16 in) in diameter and 15.5 m (51 ft) tall, while trees of that age grown in the open are 58 to 76 cm (23 to 30 in) across and 15.2 to 19.8 m (50 to 65 ft) tall.

Silvics describes young bark as varying from silvery gray to light reddish brown or cinnamon, lustrous with darker, narrow, longitudinal lenticels, and says bark on fast-growing young trees may peel into papery strips. On older trees the bark on branches may be gray, smooth and shiny, and on the main trunk may vary from dark reddish brown to gray or almost black with inch-thick irregular scales. It says the tree's beauty makes it an important ornamental, especially at the northern and western extremes of its natural range, that it has been used successfully in strip mine reclamation because of its tolerance to acid soils, and that it has been used in erosion control.

Wood

Silvics says the wood has limited usefulness and is used mainly for local enterprises such as inexpensive furniture, basket hoops and turned articles, and that its strength makes it suitable for artificial limbs and children's toys. It says experiments in North Carolina did not indicate that the species is desirable for commercial pulpwood, though naturally occurring merchantable-sized trees are often harvested for pulpwood when mixed with other bottomland hardwoods. The handbook gives a weight of about 560 kg per cubic metre (35 lb per cubic foot) and says that is somewhat lighter than commercially important birches. The Wood Handbook (FPL-GTR-282, 2021) names river birch among other birches of some commercial importance, after yellow, sweet and paper birch, but has no separate river birch row in Table 5-3b. The three main birches are on the paper birch page and the sweet birch page.

The green weight of the wood without bark is in the NRS-38 table, the same figure used in the log weight calculator.

Diseases, insects and damage the handbook names

Silvics (1990) says floods and floating ice periodically destroy or damage young riverbank stands, that young trees are usually free of serious disease, and that the tree is usually disease-free unless old or damaged.

Anthracnose leaf blight. Caused by the fungus Gloeosporium betularum and named as the principal leaf disease.
Christmas mistletoe. Phoradendron serotinum, called a common pest in the South because of the tree's preference for low, wet sites; see mistletoe on trees.
Insects. The handbook says river birch is host to several species of insects but has no serious insect pests, and credits the tree with high resistance to the bronze birch borer (Agrilus anxius); the guide on the bronze birch borer covers that insect.

The guide on reporting a pest in the United States and the Canada reporting page give the offices that take sightings of regulated pests. Who may apply pesticides is in pesticide licences by country.