Flora of North America species comparison

Crataegus douglasii occurs from southern and western British Columbia to the panhandle of Alaska and ranges to northern California and the Rocky Mountains of Idaho, Montana, and southwestern Alberta. Disjunct populations occur farther east in the Cypress Hills (Alberta and Saskatchewan), the Montana montane islands, and around the northern Great Lakes. In western North America, C. douglasii is found mainly near water in drier areas; in more mesic regions, it may occur in open woodlands. In the Great Lakes area, it mainly occurs in old pastures and on fencerows.

Crataegus douglasii is distinguished from C. gaylussacia by having ten stamens and is rather variable in leaf shape and size. The species is distinguished from C. okennonii by the latter usually being taller and typically more erect as well as having a usually straight, single trunk, shorter thorns, ampulliform-orbicular fruit, and often purplish crimson fall foliage. Crataegus castlegarensis is the most similar species, and beyond possessing relatively few to many multiple thorns, it is distinguished from C. douglasii by its hairy hypanthia, pedicels, and, often, fruit, which is orbicular, plump, crimson to purple in late August, ripening to deep purple (sometimes black) at a time when sympatric C. douglasii is fully black.

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

Crataegus crocea ranges from southwestern Alabama to central Florida into North Carolina; it is particularly abundant and locally common in Alachua and Marion counties, Florida.

A wide view is taken of Crataegus crocea. The typical form, which represents one pole of variation, has narrowly elliptic leaves perfectly smooth in outline, acute at the apices, the distal margins sometimes finely denticulate and larger leaves slightly incised distally. It is the most distinctive form of the species and is locally common at least in northern Florida. Other forms with similar leaves may be referred to C. frugalis and, if with larger leaves at maturity sometimes slightly incised distally, to C. recurva. Crataegus curva is a form that is somewhat similar to the type but is wider and shorter and has shorter petioles. Often, leaves of C. crocea are wider than the type form and somewhat spatulate; these represent C. villaris and C. incana, the latter with particularly dense tomentum when young. All the foregoing forms intergrade. Forms such as C. adusta Beadle, with more or less spatulate leaves often with strongly crenulate to obscurely lobed leaf apices, are intermediate with C. condigna. They are larger in all their parts than typical C. crocea.

In spite of its variability, there should usually be no difficulty separating Crataegus crocea either from C. munda or from the small-leaved C. condigna, both subser. Tenues, both of which have obviously toothed leaf margins, nor from C. lacrimata with its glabrous inflorescences and more or less eglandular bracteoles. Larger-leaved forms of C. crocea, with spatulate-cuneate blades obscurely crenate-serrate distally, may resemble the C. illudens form of C. lassa (subser. Robustae) from Selma, Alabama; they retain the smaller fruit of C. crocea.

A related, unnamed form known from northern Florida has particularly long petioles, narrowly rhombic-obovate leaf blades (that is, with the lateral vertices nearer the distal end), and more or less entire margins.

Crataegus crocea can form an attractive, delicate shrub, which should be very suitable for xeriscaping.

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