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Corylus

A collection of Corylus that was originally determined as C. avellana L. or “near it” was taken from near a nursery in Hartford County, CT—9 Jul 1909, Bissell s.n. ( GH!). The specimen has an unmounted annotation that reads “= heterophylla”, a statement that, if applying to the synonymy, is untrue. The plant does not appear to be C. heterophylla Fisch. & Trautv. because it lacks the characteristic leaf blade apex of that species (+/- truncate with a central acumination). The plant also does not appear to be C. avellana because it lacks the leaf blade outline (orbicular to broad-obovate) and has acute stipules. The specimen is vegetative and appears equivocal.

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C. cornuta
1a. Husk-like involucre 4–7 cm long, with a pronounced, tubular beak, bristly with slender spicules; branchlets without red, stipitate glands; staminate aments sessile or on very short peduncles up to 1 mm long; apex of buds acute
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C. americana
1b. Husk-like involucre 1.5–3 cm long, without a tubular beak [Fig. 487], pubescent but not bristly; branchlets with red, stipitate glands [Fig. 487]; staminate aments on a short, woody peduncles 1–5 mm long; apex of buds obtuse to rounded

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