Flora of North America species comparison

Varieties 6 (6 in the flora).

Crataegus pruinosa extends from Arkansas to Wisconsin, through the southern Great Lakes to southern New England, and, in the south, mainly in the Appalachians to northern Georgia.

In the north of its range, Crataegus pruinosa is mainly a shrub of open successional habitats but in the south may commonly be a taller tree of open or thin woodlands.

Many hawthorns have a little waxy bloom on their pomes; it is particularly prominent on Crataegus pruinosa and C. cognata compared to others. Some authors include in C. pruinosa their white-anthered counterparts, here assigned to C. cognata. Whereas C. pruinosa characteristically has entire or subentire sepal margins, some forms in the southwest of the range of the species (for example, C. calliantha Sargent, C. seducta Sargent) may have glandular-serrate sepal margins. They may represent introgression with C. coccinioides. The varieties of C. pruinosa are weakly differentiated from each other, most of them on leaf shape and size characters. The more widespread varieties constitute a range of morphotypes held together by common traits. Crataegus gaudens Sargent is a strikingly distinct form from Pennsylvania that has more or less elliptic leaves with lobes absent; it is clearly related to C. pruinosa. Note that 159. Crataegus ×coleae, a Michigan endemic, will key out here if its laterally scarred pyrenes are missed.

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

Crataegus persimilis has a large but sporadic distribution; some populations appear to be self-perpetuating. The species is widely cultivated.

Crataegus persimilis is plausibly a hybrid complex of C. crus-galli in the broad sense with C. succulenta in the broad sense. This is suggested by the glossy and subcoriaceous leaves like C. crus-galli, with larger size and broader proportions as in C. succulenta, and also dark and glossy one-year-old twigs, very dark, more or less stout one-year-old thorns, deeply incised sepal margins, and commonly pitted pyrenes (the sides usually excavated with a slit).

Included here is a substantial range of forms among which there is considerable variation in leaf shape, inflorescence indumentum, stamen number, anther color, pyrene excavation as well as other characters. The type form from near Rochester, New York, has the narrowest leaves (length/width = 1.5–2), most stamens (10–20), pink anthers, sparsely pubescent inflorescence branches, and deeply pitted pyrenes. The commonly cultivated ‘prunifolia’ form is similar but has a much broader leaf (length/width = 1.3–1.5) as well as densely pubescent or nearly tomentose inflorescence branches, and ten pink anthers. Crataegus helderbergensis resembles the last but has 10–14 white anthers and no lateral excavation to the pyrenes. Other similar taxa that are candidates for inclusion are: C. robusta, with wide leaves and nearly glabrous inflorescence branches, larger flowers (18 mm diam.), 10–20 pink anthers, plane-sided pyrenes in the type though excavated in syntype material; C. cerasina, similar, with laterally pitted pyrenes and smaller flowers (12 mm diam.). Crataegus livoniana Sargent has leaves more like C. crus-galli but barely eroded pyrenes and may not belong. Crataegus laetifica of Pennsylvania and Ohio is another similar form.

The cultivated plant is often called Crataegus prunifolia Persoon in the horticultural literature; this name is invalid because it is a later homonym of C. prunifolia (Marshall) Baumgarten, a synonym of Aronia prunifolia, the chokeberry. Crataegus persimilis, in its 'prunifolia' form is one of the more popular cultivated hawthorns. It is a handsome ornamental when well grown, with glossy foliage, striking scarlet fruit and fall color of foliage.

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