Coefficient of Conservatism:
Coefficient of Wetness:
Sandy and gravelly shores and dunes; rocky ridges, outcrops, and shores; dry sandy savannas with jack pine and oak; moist thickets and openings in coniferous forests and swamps.
This is a circumpolar species, the only one of our native roses that is also indigenous in the Old World; it has the largest total range of any species in the genus. Rosa acicularis is Eurasian, ranging into Alaska, and is octoploid (2n = 56). The American populations are hexaploid (2n = 42) and differ in various morphological tendencies; they may be called subsp. sayi (Schwein.) W. H. Lewis or var. bourgeauana Crép.
This species sometimes hybridizes with the diploid R. blanda; the tetraploid progeny are partly sterile.