Shrubs or trees, open-spreading, 4–8 (–15) m. Bark light to dark-brown, smooth. Branches ascending; twigs glabrous to sparsely pubescent, sometimes with glandular-hairs. Winter buds containing inflorescences ovoid, 3–5 × 3–4 mm, acute. Leaves: petiole glabrous to moderately pubescent, with or without glandular-hairs. Leaf-blade nearly orbiculate to narrowly ovate or ovate-oblong, often nearly angular and slightly lobulate near apex, 4–10 × 3.5–12 cm, thin to leathery, base narrowly cordate to narrowly rounded, margins coarsely and often irregularly doubly serrate, apex obtuse to acute or acuminate; surfaces abaxially glabrous to moderately pubescent, usually pubescent on major veins and in vein-axils. Inflorescences: staminate catkins lateral along branchlets on short-shoots, usually in clusters of 2–3, 4–6 × 0.5–0.8 cm; peduncles 0.5–10 mm. Nuts in clusters of 2–6, completely concealed; bracts bristly, connate at summit, lengthened into extended tubular beak.

Discussion

Subspecies 2 (2 in the flora).

Corylus cornuta was used medicinally by Native Americans as an emetic, for teething, to expel worms, to heal cuts, and as an astringent (D. E. Moerman 1986).

Selected References

None.

Lower Taxa

Corylus cornuta subsp. californica, Corylus cornuta subsp. cornuta

Key

1	Leaf blade ovate to narrowly elliptic, apex distinctly acuminate; twigs and petioles without glandular hairs; involucral tubular beak 2 times or more length of fruit; small to large shrubs of e, c, n North America.	Corylus cornuta subsp. cornuta
1	Leaf blade nearly orbiculate or broadly elliptic, apex broadly acute to obtuse; twigs and petioles usually bearing glandular hairs; involucral tubular beak less than 2 times length of fruit; large shrubs or small trees of Pacific coastal region of North America.	Corylus cornuta subsp. californica

"lengthened" is not a number.