Leaves: Whorled, simple; blades ovate, long-pointed at the tip, heart-shaped at the base, up to 1 foot long and about ⅔ as broad, smooth along the edges, dark green and smooth or sparsely hairy on the upper surface, soft hairy on the lower surface; leafstalks stout, up to 6 inches long.
Flowers: Large, showy, several in an elongated cluster, appearing in May and June, the clusters up to six inches long, each flower up to 2½ inches long, the petals white and lined with purple.
Fruit: Elongated capsules up to 1½ feet long and ¾ inch thick, brown, splitting into 2 parts to reveal several winged, hairy seeds about 1 inch long.
Wood: Light in weight, soft, coarse-grained, pale brown.
Uses: Fence posts, interior finishing, railroad ties.
Habitat: Low woods; often planted in a variety of habitats.
Range: Southern Indiana, southern Illinois, and southern Missouri, south to Texas, Arkansas and Tennessee; commonly planted elsewhere.
Distinguishing Features: The two Catalpas in Illinois are hard to tell apart. This one usually has deeply furrowed bark, shorter clusters of flowers, petals merely lined with purple rather than spotted, and leaves which are not unpleasantly scented when crushed.
SUGARBERRY Celtis laevigata Willd.
Other Names: Southern Hackberry; Mississippi Hackberry.
Growth Form: Medium tree up to 75 feet tall; trunk diameter up to 2½ feet; crown open and broad, with drooping branches.
Bark: Gray, with many conspicuous warts.
Twigs: Slender, gray or reddish-brown, smooth, sometimes zigzag; leaf scars alternate, usually crescent-shaped, slightly elevated, with 3 bundle traces.
Buds: Slender, pointed, smooth, brown or gray, up to ⅛ inch long.
Leaves: Alternate, simple; blades usually lance-shaped, long-pointed at the tip, tapering or rounded at the asymmetrical base, up to 6 inches long, less than half as broad, with few or no teeth along the edges, usually smooth or barely roughened on one or both surfaces; leafstalks up to ½ inch long, smooth or hairy.
Flowers: One to several in drooping clusters, appearing after the leaves are partly grown, greenish-yellow, without petals.
Fruit: Fleshy, ellipsoid to nearly round, reddish-orange to yellowish, about ¼ inch in diameter, with 1 seed, ripening in September or October, borne on slender, drooping stalks.
Wood: Heavy, soft, close-grained, pale yellow.
Uses: Fence posts, furniture.
Habitat: Lowland woods to dry hilltops.
Range: Virginia across to southern Missouri, south to Texas, east to Florida.
Distinguishing Features: The Sugarberry differs generally from other hackberries by its narrower, mostly toothless leaves.
HACKBERRY Celtis occidentalis L.
Other Name: Sugarberry.
Growth Form: Medium or large tree up to 80 feet tall; trunk diameter up to 5 feet; crown usually oblong, with many small branchlets.
Bark: Gray, smooth on young trees and soon bearing “warts,” becoming rough and scaly on old trees.
Twigs: Slender, gray to reddish-brown, smooth, sometimes zigzag; leaf scars alternate, usually crescent-shaped, with 3 bundle traces.
Buds: Slender, oval, pointed, brown or gray, finely hairy, about ¼ inch long.
Forest Trees of Illinois (third Edition) · The Wunder Library — complete classics, free to read, with narration.