Description: large tree up to 100 feet tall; trunk diameter up to 3 feet; crown very broad, with stiff horizontal branches; trunk relatively short and rather thick

Leaf: alternate, simple; blades with 7 or 9 lobes; lobes rounded, not bristle-tipped; leaves on same tree may show variation

Flower: staminate and pistillate borne separately, but on same tree; appearing when the leaves begin to unfold, minute, without petals, the staminate many in drooping, yellow catkins, the pistillate few in group, red

Fruit: acorns borne 1 or 2 together, with or without a stalk, the nut oblong, up to 3/4 inch long, green to greenish-brown, shiny, the cup covering up to 1/4 of the nut, yellow-brown.

Twig: slender, smooth, somewhat shiny, gray, whitish, or even purplish; pith star-shaped in cross-section; leaf scars alternate but crowded near tip of twig.

Bark: gray or whitish with gray patches, shallowly furrowed

Discussion: wood is heavy, hard, durable and pale brown; used for cabinets, fence posts, fuel and cooperage; it is the state tree of Illinois

Distinguishing Features: white oak is recognized by its grayish bark and its 5-7 round-lobed, smooth leaves which are usually whitish on the lower surface. 

Distribution: found throughout Illinois

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Description: large tree sometimes more than 100 feet tall; trunk diameter up to 8 feet; crown broad, often irregular

Leaf: alternate, simple; 3 or 5 shallow, sharp-pointed lobes; up to 7 inches long and often as broad; bright green and smooth on upper surface, paler and smooth on lower surface

Flower: staminate and pistillate flowers borne separately but on same tree, minute, crowded together in dense, round heads

Fruit: round light brown heads, about one inch in diameter, on long drooping stalks, containing many small seeds surrounded by hairs

Twig: smooth, light brown, somewhat zigzag; leaf scars alternate

Bark: reddish-brown when young, quickly breaking into thin, flat scales, falling away in sections to expose large patches of whitish or greenish inner bark

Discussion: wood is hard and strong; it is used for furniture and interior finishing; sometimes planted as an ornamental because of its rapid growth and unusual bark

Distinguishing Features: large palmately lobed leaves and the brown and gray mottled bark readily distinguish this tree

Distribution: found throughout Illinois, in natural habitats it is found in floodplain areas

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Description: up to 75 feet tall; trunk diameter up to 2 feet; crown irregularly rounded

Leaf: alternate, simple; blades rhombic to ovate, coarsely doubly toothed, paler and densely hairy on the lower surface, up to 3 onches long, acute at the tip, truncateor tapering to the base, the leafstalks woolly

Flower: staminate and pistillate on same tree, inconspicuous, opening in late April and May, the staminate in slender drooping clusters, the pistillate in short, conelike, woolly clusters

Fruit: tiny, hairy nuts, each with a 3-lobed wing, crowded together in a cylindrical cone up to one and a half inches long and a half inch thick

Twig: slender, reddish-brown, with several short hairs; leaf scars alternate, half-elliptical, with three bundle traces

Bark: curling, shredding, brownish-pink to reddish-brown

Discussion: wood is used for furniture; sometimes planted as an ornamental

Distinguishing Features: the shaggy, peeling reddish-brown bark readily distinguishes this tree from any other in Illinois, as does its rhombic, doubly toothed leaves

Distribution: southern and western Illinois

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Description: Large tree up to 150 feet tall; trunk diameter up to 5 feet; crown broadly rounded; trunk straight, columnar, not buttressed at the base.

Leaf: alternate, pinnately compound, with 15-23 leaflets; leaflets up to 3 1/2 inches long; broadly lance-shaped, pointed at the tip, toothed along the edges.

Flower: borne separately but on the same tree, appearing when the leaves are partly grown, the staminate several in thick, yellow-green, hairy catkins, the pistllate much fewer in small spikes, neither of them with petals.

Fruit: In groups of 1 or 2, spherical, up to 2 inches in diameter, green or yellow-green, slightly roughened, the husk thick, the nut very hard, oval, dark brown, deeply ridged.

Twig: stout, greenish or orange-brown, hairy, smooth and gray; pith brown, divided by partitions; leaf scars alternate, shield-shaped, elevated, with 3 bundle traces

Bark: black, thick, deeply furrowed

Discussion: the wood, which is hard, heavy, and dark brown is used for furniture, interior finishing and cabinets; the nuts are edible.

Distinguishing Features: the black walnut is recognized by its characteristic buds, its chambered pith and its fruits.

Distribution: throughout Illinois

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Description: up to 100 feet tall: trunk diameter sometimes more than three feet; crown usually pyramidal

Leaf: alternate, simple; blades shaped like 5- to 7-pointed stars, each point toothed along the edge, as much as six inches long and nearly as broad. In the autumn, the leaves turn a variety of colors, from red to yellow to purple

Flower: staminate and pistillate on same tree crowded together in rounded clusters, opening at about the same time as the leaves unfold 

Fruit: dry "ball" about one inch in diameter, covered by numerous short, often sharp projections, with many seeds, most of which are incapable of germinating

Twig: stout, often bordered by corky wigs; leaf scars alternate, half-elliptical, slightly elevated, with three bundle traces

Bark: usually dark gray and broken into scaly ridges

Discussion: lumber, furniture, flooring. The attractive leaves make this tree a handsome ornamental.

Distinguishing Features: the star-shaped leaves readily distinguish this tree

Distribution: southern Illinois

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Description: medium to tall tree to eighty feet tall; trunk diameter up to three feet; crown broadly rounded, with large spreading braches; trunk straight, columnar, often buttressed at the base

Leaf: alternate, simple; blades rather shallowly 7- to 11-lobed, the lobes bristle-tipped, dark green and smooth or somewhat hairy on the upper surface, paler and smooth or often with hairs along the veins on the lower surface, up to ten inches long, up to six inches broad; leafstalks up to two inches long, stout, usually smooth 

Flower: staminate and pistillate borne separately, but on the same tree, appearing as the leaves begin to unfold, minute, without petals, the staminate in slender, drooping catkins, the pistillate in groups of one to three

Fruit: acorns solitary or two together, with or without stalks, the nut ovoid, up to one and a half inches long, pale brown, covered less than one fourth by the cup, the cup reddish-brown, with tight scales

Twig: slender, smooth, reddish-brown; pith star-shaped in cross-section; leaf scars alternate, but clustered near the tip of the twig, half-round, slightly elevated, with several bundle traces

Bark: grayish-brown, reddish-brown, blackishh, or gray, with dark stripes

Discussion: interior finishing, furniture, fuel, fence posts

Distinguishing Features: the acorn with its very shallow, saucer-shaped cap is the best identifying characteristic for the Red Oak. The leaves are generally more shallowly lobed than those of the Black Oak, Southern Red Oak, and Scarlet Oak

Distribution: throughout Illinois

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Description: medium tree to seventy feet tall; trunk diameter up to three feet; crown broadly rounded, often with dropping outer branches; trunk straight, rather stout, usually with large, purple-brown, three-parted thorns

Leaf: alternate, often doubly pinnately compound, with many leaflets, leaflets oblong to oblong-lanceolate, rounded or slightly pointed at the tip, rounded at the slightly asymmetrical base, minutely toothed along the edges, smooth except for some hairs along the veins, up to one and a half inches long, less than half as wide

Flower: some flowers with both stamens and pistils, others with only one or the other, in elongated clusters up to three inches long, yellowish, small appearing in May and June

Fruit: elongated legumes up to one and a half feet long and up to two inches wide, flat, often twisted or curved, purple-brown, containing several seeds embedded in a thick pulp

Twig: slender, angular, reddish-brown, smooth zigzag, with three-parted or unbranched thorns; leaf scars alternate, more or less three-lobed, with three bundle traces

Bark: dark brown, deeply furrowed and scaly at maturity

Discussion: fence posts, coarse construction: a spineless form sometimes cultivated

Distinguishing Features: Honey Locust has more leaflets than any other kind of tree in Illinois. The large three-parted spines and the long fruits are also distinctive.

Distribution: throughout Illinois

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Description: medium tree to forty feet tall; trunk diameter up to one foot; crown rounded or dome-shaped, with several rather stout, spreading branches

Leaf: alternate, simple; blades ovate or ovate-lanceolate, long-pointed at the tip, narrowed or a little bit heart-shaped at the base, up to five inches long and three and a half inches broad, smooth along the edges, green and smooth on both surfaces; leafstalks smooth, up to two inches long

Flower: staminate and pistillate borne on separate trees, yellow-green, very tiny, the staminate crowded in short clusters on stalks up to four inches long, the pistillate crowded into spherical heads on short, stout stalks

Fruit: large, spherical greenish-yellow compound fruit up to six inches in diameter, containing many seeds, succulent flesh, and milky sap 

Twig: dull orange-brown, smooth, zigzag, with short, sharp auxiliary spines; leaf scars alternate, half-round, elevated, with usually three groups of bundle traces

Bark: light gray-brown tinged with orange, separating into shaggy strips

Discussion: bows, fence posts, railroad ties, tool handles; often planted as a windbreak

Distinguishing Features: the Osage Orange is distinguished by its spiny branches, its long-pointed, toothless leaves, its milky sap, and its large, spherical, yellow-green fruits

Distribution: throughout Illinois

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Description: medium tree to ninety feet tall, usually much smaller; trunk diameter up to three feet; crown narrowly pyramidal or broad and rounded

Leaf: of two types, either flat, triangular, opposite, and up to 1\16 inch long, or short and needle-like, up to 3\4 inch long, blue-green to green to yellow-green

Flower: staminate and pistillate on different trees, the staminate in small, narrow yellowish spikes, the pistillate in small, ovois, purplish clusters

Fruit: berry-like, spherical, up to 1\4 inch in diameter, dark blue with a whitish covering

Twig: slender, brown

Bark: reddish-brown, splitting into long shreds

Discussion: wood is durable, light in weight, red and fragrant; it is used for clothing chests, pencils and fence posts.

Distinguishing Features: the two types of leaves readily distinguish this species

Distribution: found throughout Illinois

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Description: large tree to over 100 feet tall; trunk diameter up to eight feet; crown open and spreading to pyramidal; base of trunk often swollen; "knees" usually produced if tree is growing in water

Leaf: needless borne singly, pointed at the tip, up to 3\4 inch long, yellow-green, falling away during autumn

Flower: staminate borne in branched clusters up to five inches long, purplish, pistillate few to several near the ends of the twigs, spherical

Fruit: cones nearly spherical, up to one inch in diameter, green to brown, wrinkled in appearance

Twig: slender, reddish-brown; leaf scars absent

Bark: pale reddish-brown, broken into numerous thin scales, becoming fibrous

Discussion: railroad ties, fence posts, barrels, bridges; often planted as an ornamental

Distinguishing Features: Bald Cypress is distinguished by the feathery appearance of its leaves and by its spherical, wrinkled cones

Distribution: southern Illinois

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Description: tall tree well over 100 feet tall in some regions of the United States; trunk diameter sometimes in excess of three feet; crown pyramidal

Leaf: needless in clusters of five, very flexible, up to five inches long, blue-green

Flower: staminate, crowded in several yellow spikes up to 1\3 inch long; pistillate crowded in to fewer groups, pink to purple

Fruit: cones oblong, curved, drooping, up to eight inches long, each scale comprising the cone lacking any prickles; seeds narrowly oblong, up to 1\4 inch long, with a wing up to 3\4 inch long

Twig: slender, orange-brown, smooth or slightly hairy

Bark: brown, divided into broad ridges by shallow fissures

Discussion: interior finishing, construction

Distinguishing Features: the soft, blue-green needles in clusters of five readily distinguish the White Pine

Distribution: northern Illinois

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Description: medium to large tree up to 100 feet tall; trunk diameter up to five feet; crown usually broadly rounded  

Leaf: opposite, simple; blades up to eight inches long, nearly as broad, deeply palmately five-lobed, the edges of the leaves sharply toothed, pale green and smooth on the upper surface, silvery-white and usually smooth on the lower surface, except in the leaf axils; leafstalks smooth, up to five inches long, often reddish

Flower: staminate and pistillate borne separately, but sometimes on the same tree, in dense clusters, greenish-yellow, opening in February and March before the leaves begin to unfold

Fruit: borne in pairs, composed of a curved wing with a seed at the base, green or yellow, up to three inches long

Twig: slender, reddish-brown, smooth, often curving upward; leaf scars opposite, U-shaped, with three to seven bundle traces

Bark: gray or silvery, smooth at first, becoming loose and scaly or even somewhat shaggy when old

Discussion: furniture; sometimes grown as an ornamental, but the branchlets are brittle

Distinguishing Features: the deeply lobed leaves which are silvery-white on the flower surface best distinguish this tree

Distribution: throughout Illinois

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Description: medium tree up to seventy feet tall; trunk diameter up to three feet; crown oval or rounded

Leaf: opposite, simple; blades up to six inches long, nearly as broad, palmately 3- to 5-lobed , the edges of the leaves sharply toothed to nearly toothless, pale green and smooth on the upper surface, white or gray and either smooth or hairy on the lower surface; leafstalks smooth or finely hairy, up to four inches long  

Flower: staminate and pistillate borne separately, but sometimes on the same tree, in dense clusters, bright red or yellow, opening in February and March before the leaves begin to unfold

Fruit: borne in pairs, composed of an erect wing with a seed at the base, red or yellow, up to one inch long

Twig: slender, mostly smooth, more or less reddish, usually with pale lenticels; leaf scars opposite, U-shaped, with three to seven bundle traces 

Bark: gray and smooth when young, becoming darker and scaly

Discussion: furniture, gun-stocks

Distinguishing Features: the Red Maple is characterized by its white lower leaf surfaces and its shallowly lobed leaves. The similar Silver Maple has very deeply lobed leaves

Distribution: southern Illinois

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Description: large rapidly growing tree up to 100 feet tall; trunk diameter up to 8 feet; crown spreading or broadly rounded

Leaf: alternate, simple; blades to 5 inches long and often nearly as broad, triangular, abruptly pointed at the tip; coarse rounded teeth along the edges, green, smooth, and shiny on the upper surface, paler on lower surface

Flower: staminate and pistillate borne on separate trees, the staminate crowded in rather thick, reddish catkins, the pistillate crowded in narrower, greenish-yellow catkins, both sexes appearing before the leaves begin to unfold

Fruit: elliptical, greenish-brown capsules up to 1/4 inch long, grouped in elongated clusters, containing numerous seeds with cottony hairs attached

Twig: yellow-green, gray, or tan, smooth, moderately stout, with numerous pale dots; leaf scars alternate, triangular

Bark: smooth and gray when young, becoming furrowed at maturity

Discussion: the wood is light weight, soft and warps readily; it is used for pulpwood and fuel

Distinguishing Features: easily recognized by its triangular leaves with flattened leafstalks; the cottony seeds, when the fruits are mature, are also distinctive

Distribution: throughout Illinois; found naturally in floodplain forests

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