Mapping is provisional; many more records exist. This widespread North American hexaploid (2n = 60) has been considered close to the Eurasian aviculare, possibly with some intergradation (FNA 5), but it may be closer to ramosissimum and prolificum. The species is concentrated in mid-temperate to boreal zones (PL), on disturbed sites of various types, including shorelines of rivers or ponds, city parks and roadsides (especially salted areas), but apparently much less common in farmland (unlike aviculare). It has been generally overlooked in Ky., and probably occurs throughout the state, especially along roads and sidewalks. The type is from close to the Ky. border in Lee Co., Va., "about Cumberland Gap... altitude 1500 feet" (J.K. Small, 27 Jul 1892, at NY). The species was collected by B from "banks of Dry Run" in KENT (US). Other records are somewhat tentatively mapped here, pending deeper review of the aviculare complex. Based on recent revision (FNA 5, Costea & Tardif 2004), buxiforme differs from other taxa of the aviculare complex in its ocreae, which have relatively persistent silvery distal parts (versus soon disintegrating into fibers). Also, its flowers are less elongated (l/w = 0.9-1.5 versus 1.5-2.9), and outer tepals are distinctly cucullate (pouched) at base (versus less so), often exceeding inner tepals in fruit (versus equalling or shorter). Plants are prostrate to ascending or erect, often more robust (with stems up to 0.7-2 m long and 5 mm wide), homophyllous or nearly so, and grayish- or bluish-green. Cucullate outer tepals also occur in ramossissimum and prolificum, which have ascending to erect habit and narrower leaves (l/w mostly 4-12 versus 2.5-6).