Crataegus × incaedua

From Flora of Indiana (1940) by Charles C. Deam

Leaves ovate or elliptic, mostly 3-7 cm long, and 2-5 cm wide, obtuse, acute or short-acuminate at the apex, cuneate at the base and tapering into short (0.3-1 cm) petioles, coarsely serrate except near the base, undivided except rarely on shoots, firm to subcoriaceous and with veins slightly impressed above at maturity, dark green and scabrate above when young, paler and pubescent beneath; flowers 15-18 mm in diameter, usually 8-20, in lax, compound, villous corymbs; stamens usually 10-15; anthers pale yellow; fruit subglobose or oblong, 8-12 mm in diameter, red at maturity, sometimes slightly glaucous; calyx lobes serrate or glandular-serrate, reflexed; nutlets 2-3, usually 2, sometimes with shallow pits on the ventral surfaces. A tree up to 6-7 m high, with pale brown gray bark and ascending or spreading branches, forming a low, conical crown; branchlets villous the first season, becoming gray, usually armed with numerous, long, curved thorns. Crataegus incaedua is probably a hybrid between Crataegus calpodendron and Crataegus crus-galli or some species of the Crus-galli group. Known in Indiana only from Harrison County, where it was found along a small creek at the base of a rocky, wooded slope about a mile south of Corydon Junction.