Flora of North America species comparison

Crataegus flabellata occurs along the Niagara Escarpment in Ontario, on both sides of Lake Ontario and the St. Lawrence, to New Brunswick and Nova Scotia, and to Massachusetts. Reports for Newfoundland have not been substantiated.

Crataegus flabellata is distinctive with its leaf blades glossy dark green, ovate to broadly elliptic, cuneate at the base, and with deep acuminate lobes. Specimens with less glandularity or serration of the sepal margins may resemble C. fluviatilis. In spite of the obvious differences in morphology and range, C. flabellata and C. macrosperma often have been combined by floristicians. From C. chrysocarpa, C. flabellata is distinguished by its shinier, ellipsoid, glabrous fruit, by the usually deeper, acuminate lobes of its glossy, dark green leaves, and by longer, slightly more acute sepals. Typically, the inflorescences and hypanthia of eastern C. chrysocarpa are densely hairy, practically tomentose, unlike C. flabellata with its more sparsely hairy pedicels and glabrous distal hypanthia. It is conceivable that, due to morphological intermediacy and the sympatry of all three species within the range of C. flabellata, this species represents the result of ancient hybridization between C. chrysocarpa and C. macrosperma.

Crataegus flabellata is usually divided into two varieties: var. flabellata (10 stamens) and var. grayana (20 stamens), the latter being particularly common in southern Quebec. There appears to be little, if any, other constant differentiating feature. Crataegus crudelis, also from Quebec, is a form recognized by long thorns (to 10 cm).

The name Crataegus densiflora Sargent, which pertains to C. flabellata, is illegitimate.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Crataegus punctata is a common northeastern North American hawthorn, ranging across the northeast quarter of the United States and adjacent Canada to New Brunswick, to North Carolina and Tennessee, occurring mainly above 1000 m in the southern Appalachians. South of New Jersey, it is not found near the coast. The species may occur in nearly pure populations of up to several thousand individuals. The best growth is in sunny sites near streams.

Crataegus punctata is recognized among sympatric species by its matte green leaves (unlike the somewhat similar C. crus-galli) with impressed veins, tabulate branching when grown in the open, usually burgundy fruits with pale dots; the whitish or ashy gray twigs present a distinctive feature in winter (J. B. Phipps et al. 2003, plate 55), responsible for the common name white haw. The similar C. collina, with an allopatric distribution and much earlier flowering season, is often confused with it but is readily differentiated (see key and discussion for that species). Extension-shoot leaves of C. punctata may be very deeply incised with veins to the sinuses, a characteristic not found in C. collina.

Some forms of Crataegus punctata bear scarlet or yellow (var. aurea Aiton) fruit. Hairier forms, especially hairier leaves, have been named var. canescens Britton; very small-leaved forms have been called var. microphylla Sargent. Nearly glabrous forms, all with somewhat glossy foliage, less coarse leaf toothing than C. punctata, and ten stamens, occur sporadically and have been named C. grandis Ashe and var. pausiaca (Ashe) E. J. Palmer. They are probably hybrids with C. crus-galli, as is the similar C. ×disperma, treated under interserial hybrids. The very rare C. ×puberis Sargent is perhaps a hybrid with C. macrosperma, C. ×kellermanii Sargent a hybrid with C. pruinosa, and C. ×neobaxteri Sargent a hybrid with a species of ser. Rotundifoliae.

(Discussion copyrighted by Flora of North America; reprinted with permission.)