Ohio Trees

Bulletin 700-00

Quercus – Oaks

Oaks are deciduous or evergreen trees with scaly buds that are clustered at the ends of the twigs. Leaves are alternate with lobed, toothed, or entire margins. Flowers are monoecious. Male flowers are borne in catkins. Fruits are nuts (acorns). Evergreen forms are not cold-hardy in Ohio.

Key to Quercus Species

Description of Species

	White Oak

White Oak–Quercus alba

The white oak is one of the most important timber trees. Its natural range includes almost the entire eastern half of the United States. It reaches a height of 60—100 feet with a diameter of 2—3 feet or more, and it sometimes becomes much larger. It is found in a wide variety of soils. When grown in a dense stand, it has a straight, continuous trunk, free of side branches for over half its height. In the open, however, the tree develops a broad crown with far-reaching limbs and will be wider than it is tall. Well-grown specimens are strikingly beautiful.

The leaves are alternate, simple, 4—8 inches (10—20 cm) long, and about half as broad. They are deeply divided into five to nine rounded, fingerlike lobes. Expanding leaves are soft and silvery gray, yellow, or red when unfolding. Mature leaves are bright green above and much paler below. Leaves are glabrous, or only slightly hairy beneath. Petioles are more than 1/2 inch (13 mm) long. Leaves are usually wedge-shaped at the base.

Buds are less than 1/4 inch (6 mm) long and light brown in color, with rounded tips. Twigs are slender, shiny, and purplish in color. Twigs are glabrous and sometimes covered with a waxy bloom. The bark is thin and light ash gray with mature bark covered with loose scales or broad plates.

The fruit is an acorn which matures the first year. The elongate nut is 3/4—1 inch (19—25 mm) long and light brown in color. About one-quarter of the acorn is enclosed in the warty cup. It is relished by hogs and other livestock. The acorns are a major source of food for wildlife such as deer and squirrels.

The wood is useful and valuable. It is heavy, strong, hard, close-grained, and durable. The color of the wood is light brown. The uses are many, including construction, shipbuilding, tight cooperage, furniture, implements, interior trim, flooring, and fuel. White oak is valuable for ornamental planting because of its urban-tolerance, storm resistance, and pest resistance. This tree is not commonly grown by nurseries since it is reported to be difficult to transplant and is rather slow-growing when small. Once established, the tree grows rapidly.

	Swamp White Oak

Swamp White Oak–Quercus bicolor

The swamp white oak inhabits the bottom or lowlands, and generally has the same appearance as the white oak when mature. When it is young, the swamp white oak has a more regular habit of growth. It is found in the flood plains and along streams in most areas of the state except the southeastern section where it is uncommon. The rounded habit of the young tree gives way to a massive, spreading, tree that may exceed 80 feet in height.

The mature bark is deeply and irregularly divided by fissures into broad ridges of a gray-brown color. Buds are rounded and about 1/8 inch (3 mm) long. Current year's twigs are a dull, yellowish-brown, and glabrous. Older twigs are light gray, scaly, and exfoliating. Twigs may be winged as is the bur oak. Trees are heavily branched, and twigs may have corky ridges. Intermediate bark is a light grayish-brown, fissured, and scaly.

Leaves are coarsely toothed or shallowly lobed with six to eight pairs of lobes. Foliage is 4—6 1/2 inches (10—16 cm) long and 2—4 inches (5—10 cm) wide. The outline of the leaf is oblong to obovate. The leaves are generally broader at, or above, the middle of the leaf blade (pear-shaped). The base of the leaf is acute and/or wedge-shaped. The leaf margins are wavy and indented. Foliage color is dark green and shiny above and grayish beneath. Leaves are woolly or hairy beneath. The contrasting colors of the upper and lower leaf surfaces give rise to the species name (bicolor).

Flowers are monoecious and open in May. The acorn, or fruit, occurs commonly in pairs and, like all of the white oak group, requires only one season to mature. The nut is borne on slender stalks (peduncles) from 2—4 inches (5—10 cm) in length. The acorn is about 1 inch (21/2 cm) long and 2/3 inch (17 mm) thick. It is enclosed for about one-third its length in a thick, unfringed cup.

The wood is heavy, hard, and strong. Lumber is used for similar purposes as the true white oak which includes furniture, cabinet work, flooring, cooperage, ties, fence posts, and fuel.

		Scarlet Oak

Scarlet Oak–Quercus coccinea

Scarlet oak occurs abundantly on dry, rocky, and sandy soils throughout the uplands and ridges of southeastern Ohio. It is not common in other parts of the state. It usually reaches a height of 60—80 feet with a trunk diameter of 2—3 feet although sometimes larger. The branches droop at the ends and form a narrow, open crown.

The largest terminal buds are usually 1/4 inch (6 mm) or more in length. The bark on young stems is smooth and light brown. On older trunks it is grayish-brown and divided into ridges. The mature bark is not as rough as that of the black oak. The bark is often mottled or spotted. Pointed buds are dark reddish-brown and usually hairy above the middle of the bud. Twigs are reddish and glossy. The inner bark is reddish.

The leaves are simple, alternate, 3—6 inches (71/2—15 cm) long, 21/2—4 inches (6—10 cm) wide, and nearly square at base. Leaves are usually oblong or oval and seven-lobed. The lobes are bristle-pointed and separated by round openings (sinuses) that extend two-thirds of the distance to the midrib, giving leaves a deeply "cut" appearance. Leaves have small, inconspicuous, axillary tufts of hairs in the axils of the veins beneath the leaf. The leaves turn a brilliant scarlet in the autumn and give the tree its common name.

The flowers are monoecious and appear when the leaves are one-half to two-thirds grown. Like other red oaks, the fruit takes two years to mature. The acorn is 1/2—1 inch (13—25 mm) long, reddish-brown, and often striped. When viewed from the end, the stripes on the acorn form small Cs at the point of the fruit. About one-half of the acorn is enclosed in the cup.

The wood is heavy, hard, strong, and coarse-grained. The lumber is sold as red oak and has the same uses. Scarlet oak is urban-tolerant and useful for ornamental planting but is reported to be difficult to transplant. It is uncommon in nurseries.

Southern Red (Spanish) Oak–Quercus falcata (rubra)

The southern red oak is also commonly known as Spanish oak. Spanish oak usually grows to a height of 70—80 feet and a trunk diameter of 2—3 feet. Larger trees are not uncommon. It is one of the rarest of the native Ohio oaks and is found only in Scioto, Lawrence, and Jackson counties. Its large-spreading branches form a broad, round, open top.

Southern Red (Spanish) Oak

Leaves are elliptic to oblong and not wider at the tip of the leaf as is the blackjack oak. Foliage is 3—8 inches (71/2—20 cm) long with three to seven narrow lobes that are often sickle-shaped. The leaves are of two different types: (1) irregular-shaped lobes, mostly narrow and bristle-tipped with the central lobe often being the longest; or (2) pear-shaped with rounded and bristle-tipped lobes at the outer end. Foliage is dark, lustrous green above and whitish to grayish-green and tomentose beneath. The contrasting colors are strikingly seen in a wind or rain storm.

Twigs are reddish-brown and angled with pointed buds. A rusty-woolly pubescent may or may not be present. Overwintering buds are 1/4 inch (6 mm) long, reddish-brown, and pubescent toward the tip. The bark is rough, though not deeply furrowed, and varies from light gray on younger trees to dark gray (almost black) on older ones. The bark is rich in tannin.

The flowers appear in April while the leaves are unfolding. The fruit ripens the second year. The small, rounded acorn is about 1/2 inch (13 mm) long and set in a thin, saucer-shaped cup which tapers to a short stem. This tree has an unusually small acorn. Heavy crops of seed occur every 3—5 years.

The wood is heavy, hard, coarse-grained, and less subject to defects than most other red oaks. It is used for rough lumber and for furniture, chairs, and tables. It is a desirable timber tree, especially on the poorer, drier soils.

	Shingle Oak

Shingle Oak–Quercus imbricaria

The shingle oak is found scattered over the entire state, usually growing as an individual. When growing alone, the tree develops a symmetrical, rounded crown. Young trees have drooping lower branches, lateral middle branches, and ascending upper branches. Young trees often retain the russet foliage through the winter and into spring when the old foliage is pushed off by the new foliage.

It forms a handsome tree. It is sometimes incorrectly called a "laurel" oak. The tree may exceed 80 feet in height. Shingle oak is one of the more commonly planted red oaks in Ohio. It is urban-tolerant and can be used as a street tree. The tendency to retain foliage during the winter, combined with the drooping lower branches allow this tree to serve as a large screen.

Foliage is unique among native red oaks as this tree has an entire leaf rather than the lobed margins more commonly seen. The alternate leaves are oblong in shape. Leaves are 23/4—61/2 inches (7—161/2 cm) long by 1—2 inches (3—5 cm) wide. Leaves are leathery in texture; shiny, dark green above; and pale green or brownish and pubescent below.

Twigs have the cluster buds that say oak. Twigs are greenish in color with small, pointed buds. Bud scales are hairy. The bark is thin and divided into broad, dark brown ridges by shallow fissures. Mature bark is similar to other red oaks and is dark gray and deeply furrowed.

The fruit is an acorn about 1/2 inch (13 mm) in length, borne singularly or in pairs. Acorns are rounded at the end, faintly streaked, and enclosed for about half of its length in a thin-walled cup. Like all members of the red oak group, the fruit requires two seasons to mature. This tree has an unusually small acorn. Heavy crops of seed occur every 3—5 years.

The wood is heavy, hard, and coarse-grained. It is used for common lumber, shingles (whence it got its common name), posts, and firewood. The tendency to retain lower branches makes this tree less valuable for lumber but the lumber is marketed as red oak.

	Bur (Mossycup) Oak

Bur (Mossycup) Oak–Quercus macrocarpa

The bur oak occurs throughout the state, although it is chiefly confined to the central and western portions. In the eastern portion of Ohio it is rare and found only occasionally along streams in lowlands. It usually has a broad top of heavy, spreading branches and a relatively short body. At maturity, the tree attains a diameter of 5 feet or more and a height of over 80 feet.

Unlike other oaks, the bur oak is not often a part of the oak-hickory forest stand. It generally occurs in open stands (oak openings) and in fields. In fire-dominated landscapes such as oak openings, the bark is thick, deeply fissured, and quite fire resistant. The bur oak is more alkaline-soil-tolerant than many other oaks.

The leaves resemble those of the common white oak and have rounded lobes. Bur oak differs in that it has a pair of deep sinuses toward the base and wavy notches on the broad, middle, and upper portions of the leaf. Leaves are said to be fiddle-shaped. They range from 6—91/2 inches (15—24 cm) long and 3—6 inches (71/2—15 cm) wide. Leaves are glabrous and shiny with a deep green color on the upper leaf surface.

Twigs are pubescent and gray or yellowish-brown in color. Two-year and older twigs are often winged. Rounded buds are less than 1/4 inch (6 mm) in length, rounded in outline, and often flattened against the twig. The mature bark is light gray, usually broken up into small, narrow flakes, and is thinner when fire is not a factor.

Bur oak takes its name from the fringe around the cup of the acorn. The fruit, or acorn, is deeply set in a fringed cup. These acorns are the largest of the oaks and are sometimes 1 inch (25 mm) or more in diameter. Acorns do vary widely in size and the degree to which the nut is enclosed in the mossy fringed cup. Heavy crops of seed occur every 3—5 years and are a major food source for deer and other wildlife when abundant.

The wood is heavy, hard, strong, and durable. It is used for much the same purposes as the other white oaks, including lumber, crossties, and fuel.

	Blackjack Oak

Blackjack Oak–Quercus marilandica

The occurrence of blackjack oak is said to indicate poor soil. It is certain that blackjack oak often occurs on dry, or poorly drained, gravel, clay, or sandy, upland soils where few other forest trees thrive. This may account for the tree's slow rate of growth. It is found locally in the extreme southeastern part of the state, usually on sharp ridges where it is associated with scrub pine, scarlet oaks, and chestnut oaks.

The tree sometimes reaches heights of 50—60 feet and a trunk diameter of 16 inches, but it is usually much smaller. Blackjack oak's hard, stiff, drooping branches form a dense crown which usually contains many persistent, dead twigs.

The bristle-tipped leaves have a leathery texture. They are dark green on the upper surface and lighter beneath. Leaves are broadly obovate with three to five lobes, mostly at the apex. Leaves are often rusty-woolly beneath. Foliage is 4—8 inches (10—20 cm) long and nearly as broad at the apex.

The pointed overwintering buds are borne in clusters and are 1/4—1/3 inch (6—8 mm) long. Buds are reddish-brown and woolly. Twigs are usually dull, reddish-brown, becoming ash gray. The bark is rough, very dark (often nearly black), and broken into small, hard scales, or flakes.

Flowers are monoecious and open in May. The fruit is an acorn about 3/4 inch (19 mm) long, yellowish-brown in color, and often striped. The acorn is enclosed for at least half its length in a thick, light brown cup. Acorns take two years to mature.

The wood is heavy, hard, and strong but not commonly used in commerce because of its small size and branchy crown. When the wood is used at all, it is used mostly for firewood and mine props.

	Chinquapin Oak (Yellow Oak)

Chinquapin Oak (Yellow Oak)–Quercus muhlenbergi

This oak is an excellent timber tree and occurs throughout the state, but it is more abundant in the southwestern portion. It grows on practically all classes of soil and in all moisture conditions except swamps, and is a very tenacious tree on shallow, dry soil. This tree is an indicator of alkaline soils. It reaches heights of 70—90 feet and is one of the largest oaks native to Ohio. The straight, shapely trunk bears a round-topped head composed of small branches, which makes it an attractive shade tree. The nursery industry rarely offers this tree, in part because it is reported to be difficult to transplant.

The leaves are oblong, 4—61/2 inches (10—161/2 cm) in length and 11/2—3 inches (4—71/2 cm) wide. The leaf margins are regularly toothed or notched and frequently have glandular tips. The teeth are more acute-tipped and are more American chestnut-like than chestnut oak. Leaves are dark green above and whitish beneath. The foliage texture is finer than most other oaks. Leaves are not lobed, as are most oaks.

The largest terminal bud is less than 1/4 inch (6 mm) long. Buds are generally rounded and a pale brown color. Twigs are slender, rounded, and glabrous. The mature bark is light gray and breaks up into short, narrow flakes on the main trunk and older limbs.

Chinquapin oak has monoecious flowers. The fruit ripens in the fall of the first season and is light to dark brown when ripe and edible if roasted. This acorn is from 1/2—1 inch (13—25 mm) long, usually not as wide, and set in a shallow cup. This is one of the smallest acorns of our native white oaks. The seed is very attractive to wildlife who readily harvest it. It is difficult to beat the wildlife to the seed and therefore this desirable tree is rarely found in nurseries.

The wood is heavy, very hard, strong, durable, and takes an excellent polish. It is used for timbers, crossties, fence posts, fuel, and furniture.

	Pin Oak

Pin Oak–Quercus palustris

Pin oak is found naturally on the rich, moist soil of bottom lands and borders of swamps. While not common on a statewide basis, it is often found growing in pure stands on wet, heavy, clay soils. The pin oak "flats" of Brown, Clermont, Warren, and Hamilton counties in southwestern Ohio are examples of local abundance.

Pin oaks commonly attain heights of 50—70 feet with trunk diameters up to 2 feet or more. The tree normally has a single, upright stem with numerous long, tough branches. The many small, bristling twigs and branches give the tree its name.

Fall color ranges from russet to orange and may be showy. Because of its beauty, hardiness, urban-tolerance, and fairly rapid growth, the pin oak makes a good ornamental tree. Care must be taken to plant trees that are from locally adapted seed sources. Native pin oaks are adapted to Ohio's neutral soils and rarely show an iron deficiency. Iron deficiencies are common on seedlings from areas such as Tennessee where the parent trees are adapted to acid soils.

Pin oak has a pyramidal habit with a straight, central stem when less than 12 inches (301/2 cm) in diameter. Lower branches droop, the middle branches are lateral, and the upper branches ascend. Older trees have the typical habit of the red oak group and broaden with age to become as broad as they are tall.

The leaves generally resemble those of scarlet oak, except their rounded openings do not extend so near to the midrib, and their size is somewhat smaller. Leaves are 3—5 inches (71/2—12 cm) long and 2—4 inches (5—10 cm) wide. Leaves are glossy, deep green above and light green beneath. Leaves have conspicuous tufts of hair in the axils of the veins beneath. The leaf base is wedge-shaped.

Buds are not velvety tomentose, but are light brown and glabrous, or only slightly hairy. The largest terminal buds are usually less than 1/4 inch (6 mm) in length. Winter buds and twigs are reddish with greenish inner bark. The bark on young trees is smooth, shiny and light brown. On old trunks bark is light grayish-brown, fissured, and covered by small, close scales.

The monoecious flowers appear when the leaves are about one-third grown. The female flowers take two years to mature into an acorn. Male catkins are borne on the same tree. The fruit is a hemispherical acorn, about 1/2 inch (13 mm) long. The acorn is light brown in color, often striped, and enclosed at the base in a thin, shallow, saucer-shaped cup. This tree has an unusually small acorn. Heavy crops of seed occur every 3—5 years.

	Willow Oak

The wood is heavy, hard, strong, and usually knotty. It is light brown with thin, darker-colored sapwood. It is sold for the same uses as other red oaks, but is generally not as good in quality due to the tendency to retain the lower branches.

Willow Oak–Quercus phellos

Willow oak is a tree that reaches 80 feet in height and is quite similar to its relative, the native shingle oak (Quercus imbricaria). It is reported locally in Jackson and Scioto counties but may be escaped in those counties. The native range is southward, where it is common in Kentucky and Tennessee. It is found not only in lowlands and along borders of rivers and swamps but also on rich, sandy uplands.

It is a beautiful, long-lived tree and is much desired for roadsides, lawns, and park plantings. It is the most common shade tree in the middle South and gives way to the live oak in the deep South.

Leaves are entire and quite different than most oaks. The leaves of the willow oak are narrower and more willowlike than the shingle oak. The slender willowlike leaves on a tree whose growth habit is manifestly that of a red oak make the tree easy to identify. The leaves are 2—4 inches (5—10 cm) long and 1/2—3/4 inch (13—19 mm) wide with smooth or slightly wavy margins. Like other red oaks, the end of the leaf is bristle-tipped. Leaves are glabrous, shiny, light green above and dull below, and the leaf arrangement is alternate.

Twigs are fine-textured and have small, pointed buds less than 1/4 inch (6 mm) long. The imbricate buds are glabrous. Twigs are reddish-brown in color when young. The bark generally remains smooth for a number of years, becoming gray in color. With age, the bark becomes slightly roughened and divided by narrow ridges.

The small acorns are closely set along the stem, and mature at the end of the second year. The nut is a light brown hemisphere about 1/2 inch (13 mm) in diameter with its base scarcely enclosed in the shallow, reddish-brown cup. The fruit is small when compared to most other oaks. The nuts are eaten by blue jays, grackles (blackbirds), and several other species of birds, as well as by rodents. Oaks generally bear fruit heavily every 3—5 years and lightly, or not at all, in other years.

The wood is not separated commercially from other species in the red oak group. It is heavy, strong, rather coarse-grained, light brown tinged with red, and not durable when exposed to the weather. It is used locally for crossties, bridges, planks, barn sills, and general construction.

Chestnut Oak–Quercus prinus (montana)

	Chestnut Oak

Chestnut oak is also known as mountain oak and rock oak because its leaf resembles that of the chestnut and because of its fondness for rocky mountain ridges. It is found widely distributed in the hilly areas of southern and eastern Ohio, on dry, rocky slopes and ridges. It is uncommonly found in rich mesic sites, but where it is found, it looks like another, more massive tree.

On poor sites it is a spreading tree reaching 30—50 feet. Its trunk frequently divides into several large, angular limbs making an open, irregular-shaped head. On good sites, the chestnut oak becomes a massive tree, growing to 80 feet in height with a spreading crown somewhat like the white oak. In 1997, the largest chestnut oak in Ohio was almost 5 feet in diameter (trunk), 129 feet in height, and 110 feet across.

The leaves are 4—61/2 inches (10—161/2 cm) long, simple, and alternate. Leaf shape is oblong, rounded at the tip, and irregularly scalloped, or wavy, on the margin (not sharp-toothed as in chinquapin oak). Foliage is normally widest, at or above, the middle of the leaf. Foliage is a shiny, yellowish-green color above and lighter green, white, and woolly beneath.

Twigs are glabrous. Buds are acute-tipped and large (1/4 inch [6 mm] long or longer). Buds are slightly pubescent, or ciliate, above the middle of the bud. The bark is dark, reddish-brown, thick, and deeply divided into broad, rounded ridges on older trees.

The May flowers are monoecious and similar to those of the white oak. The fruit is an acorn about an inch (25 mm) long, oval, shiny brown and enclosed to half its length in a cup. The acorn is longer than it is wide. It ripens in one season, and like the acorn of the white oak, sprouts in the autumn soon after falling to the ground. The cup is thin, deep, and hairy inside.

The wood is generally similar to that of the other upland white oaks which is heavy, hard, strong, and durable, especially in contact with the soil. It is extensively cut into crossties and heavy timbers for bridges, railroad tracks, and other rough construction. It is also used for fence posts and fuel.

Eastern Red Oak–Quercus rubra (borealis)

	Eastern Red Oak

The eastern red oak occurs throughout the state, but is more abundant and of better quality in the heavy, clay soils of the northwest, central, and northeast portions of the state. It is of mesic sites and not found in swamps. It normally attains a height of about 70 feet with a diameter of 2—3 feet, but is sometimes much larger. The forest-grown tree is tall and straight with a clear trunk and narrow crown.

The simple, alternate, leaves are 43/4—83/4 inches (12—22 cm) long, 4—6 inches (10—15 cm) wide, wedge-shaped at the base, and lobed about halfway to the middle. The leaf is broader above the middle of the leaf blade. The blade is divided into seven to nine lobes (each lobe being somewhat coarsely toothed and bristle-tipped). Leaves are dull green above and paler below. Fall color ranges from a russet to a brilliant red.

Twigs are shiny and reddish, as the name suggests, in the winter. Reddish buds are clustered, 1/4 inch (6 mm) long, ovate, and slightly hairy. The bark on young stems is smooth and from gray to green in color. Mature bark is thick, gray, and broken by shallow fissures into regular, flat, smooth-surfaced plates on older trees. Unfissured patches of bark are common on the mature bark of Eastern red oak.

The flowers, as in all the oaks, are monoecious. The male is long, drooping, clustered catkins opening with the leaves. The female flowers are solitary or slightly clustered. The fruit is a large acorn that matures the second year. The nut is globose and from 3/4—11/4 inches (19—32 mm) long with blunt tips and a flat base. Only the base of the acorn is enclosed in the shallow, dark brown cup.

The wood is hard, strong, and coarse-grained with light reddish-brown heartwood and thin, lighter-colored sapwood. It is used for interior finishes, construction, furniture, and crossties. Because of its rapid growth, high-grade wood, and relative freedom from insect and disease attack, it is widely planted as a shade tree.

		Post Oak

Post Oak–Quercus stellata (minor)

The post oak is usually a medium-sized tree with a rounded crown commonly reaching a height of 40—60 feet and a diameter of 1—2 feet. Sometimes post oaks grow considerably larger. Poor soils are favored by this tree. It occurs most abundantly in southeastern Ohio from Franklin and Madison counties southward and eastward. This tree is commonly used as a landscape tree in Texas where the drought- and urban-tolerance is desired. The moderate size should make it more popular in Ohio in the future.

Buds are reddish-brown and rounded. The stout, young twigs and leaves are coated at first with a thick, light-colored fuzz, which soon becomes darker and drops away entirely. Twigs and buds are reddish-brown in color.

The leaves are usually 4—8 inches (10—20 cm) long and nearly as broad. Rounded lobes have deep sinuses and are broadest at the ends of the lobes. The outline of the leaf is somewhat cross-shaped. Foliage is thick and leathery. Leaves are shiny and dark green on the upper surface, but lighter green, rough, and pubescent beneath.

The flowers, like those of the other oaks, are monoecious. The male flowers are borne in drooping, clustered catkins. Female flowers are inconspicuous. The fruit is an oval acorn, 1/2—1 inch (13—25 mm) long, and set in a small cup which may or may not be stalked. Fruit matures in a single season and is not fringed.

The bark is rougher and darker than that of other white oaks and broken into smaller scales. The wood is very heavy, hard, close-grained, light to dark brown, and durable in contact with the soil. It is used for crossties, fence posts, furniture, and other purposes similar to other oaks of the white oak group.

Black Oak–Quercus velutina

The black oaks grow to about 80 feet in height and 2—3 feet in diameter and is a typical red- or black-oak-group tree. The large crowns are irregularly shaped and wide with a clear trunk for 20 feet or more. Its growth is rather slow. It is commonly found on dry plains and ridges. Unlike the closely related red oak, the black oak is rarely seen on rich ground. Along the old glacial shorelines in northwestern Ohio, it occurs in nearly pure stands from Lucas County westward to the Indiana line.

The leaves are alternate, simple, 4—10 inches (10—25 cm) long and 3—8 inches (71/2—20 cm) wide. Leaves may be shallowly or deeply lobed. The shape varies greatly. Leaves are similar to the red oak but are generally larger and not as deeply lobed. Lobes are bristle-tipped. When mature, the leaves are dark, shiny, and green on the upper surface and pale on the underside of the leaf. The lower leaf surface is covered with conspicuous, rusty brown hairs in the forks of the veins.

Black Oak

Buds are velvety tomentose (grayish-woolly) throughout and longer than 3/8 inches (91/2 cm) long. Twigs are brown and shiny. Inner bark of twigs is yellowish-orange in color. The bark on the very young trunk is smooth and dark brown. The bright yellow color and bitter taste of the inner bark is due to the tannic acid content of the bark and is a distinguishing characteristic. Mature bark becomes thick and black with deep furrows and rough, broken ridges.

Flowers are monoecious and open in May. The light brown nut is large (3/4—1 inch [19—25 mm] long) and hemispherical in shape. From one-half to three-quarters of the nut is enclosed in the thin, dark brown, scaly cup. The kernel is yellow and extremely bitter. The fruit matures the second season.

The wood is hard, heavy, strong, and coarse-grained. The wood checks, or cracks, easily as it dries. Lumber is a bright reddish-brown with a thin, outer edge of paler sapwood. Black oak is used for the same purposes as red oak under whose name it is marketed.