Corylus americana aka American Hazelnut

American hazelnut, Corylus americana, is a deciduous shrub in the birch family, Betulaceae. Gardeners also call it American filbert or American hazel. It grows wild across eastern and central North America. Its range runs from Newfoundland and Saskatchewan south to eastern Oklahoma and Florida. In the wild it grows in thickets, open woods, hillsides, fencerows and prairies.

This multi-stemmed shrub forms a rounded clump. Most garden plants reach 8 to 15 feet (2.4 to 4.6 m) tall. Some sources give a narrower 9 to 12 feet (2.7 to 3.7 m), and plants may grow taller in shade. Spread is often 8 to 12 feet (2.4 to 3.7 m). Root suckers let a plant widen into a thicket over time. Growth is moderate to fast, sometimes adding well over a foot a year. Young stems are hairy and the twigs zigzag. The bark starts gray and smooth, then roughens on older wood.

The leaves are alternate, simple and oval, with doubly toothed edges. They are dark green above and paler and hairier beneath. Fall color varies from bright yellow and orange to red-purple or a dull yellow-green. Male and female flowers grow on the same plant in late winter or early spring, before the leaves open. The males hang in yellowish-brown catkins up to about 3 inches (8 cm) long. The females are tiny buds with red stigmas just poking out. The plant is not self-fertile, so plant several for good nut set.

The nuts are about half an inch (1.3 cm) across. Each sits inside a leafy husk with ragged edges. They ripen from late summer into fall. Plants usually begin bearing at two or three years old. People eat the sweet kernels raw, roasted or ground into flour, and the seeds also yield an edible oil. Squirrels, deer, turkeys, grouse, songbirds and many other animals compete for the crop. The shrub also hosts caterpillars of Saturniidae moths.

American hazelnut grows easily in average, well-drained soil in full sun to part shade. Full sun gives the best nut crop. It tolerates clay, sand, acid or alkaline soil and black walnut. Once established, it copes well with drought. It is hardy in USDA zones 4 to 9. Upkeep is low, and you can prune at any time. Remove suckers if you want to stop a thicket forming. It suits naturalized areas, woodland edges, screens, hedges and the back of a shrub border.

Serious problems are uncommon. Eastern filbert blight can affect it, along with leaf spots, other blights and crown gall. Japanese beetles, scale, leafhoppers and leaf-eating caterpillars sometimes feed on it. Deer cause moderate damage, and the shrub does not tolerate salt. In the past people made a bark tea to treat hives and fevers. They also used the bark as a poultice for cuts and sores. No hazards are known for this species.