Several segregates of this widespread, variable eastern species have been described, but their treatment remains inconsistent and uncertain; there are reported diploids, triploids and tetraploids (Lance 2014; FNA 9). The map includes early records of C. armata Beadle (CAMP), C. wilkinsonii Ashe (BOON), and other names that are generally considered synonyms in some recent treatments (Cr, M). The relativly distinctive var. pyracanthifolia Ait., with narrower leaves (L/W ca. 2.5-4 versus 1.5-2), is known from w. Tenn. and may be expected in w. Ky. (Lance 2014). Although crus-gallii has been widely recorded in Ky., like several other hawthorns it has declined due to the abandonment or conversion of rougher rocky pastures and invasion of Juniperus virginiana. Extensive colonies, as still exist in some other states (Lance 2006, 2014; D. Boone, pers. comm.), are now virtually unknown in Ky. "Hot-spots" with this and other Crataegus species may indicate where open woodland occurred before settlement, or where rough pasturing continued after settlement.