This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Rosa setigera Michx. Fl. Bor. Am. 1: 295. 1803.
Stems climbing, several feet long, armed with scattered curved prickles but not bristly, or unarmed. Petioles, twigs and peduncles often glandular-pubescent; stipules very narrow; leaflets 3, or sometimes 5, mostly ovate, acute or obtusish at the apex, rounded at the base, 1'-3' long, sharply serrate; flowers corymbose, about 2 1/2' broad; calyx-lobes ovate, acute, at length reflexed and deciduous, glandular; petals obcordate, varying from rose-color to white; styles cohering in a glabrous column; fruit globose, 4"-5" in diameter, more or less glandular.
Rosa blanda Ait. Hort. Kew. 2: 202. 1789.
Erect, low, 2°-4° high; entirely unarmed or with a few straight slender prickles on the stem. Stipules rather broad; leaflets 5-7, short-stalked, usually pale beneath, oval or obovate, obtuse at the apex, commonly narrowed or cuneate at the base, 1' - 1 1/2' long, simply and sharply serrate; flowers pink, sometimes 3' broad, corymbose or solitary; calyx-lobes lanceolate, acuminate, entire, hispid-pubescent, persistent and erect on the fruit; petals obovate, erose or sometimes obcordate; styles separate; fruit globose or pyriform, glabrous or nearly so, about 5" in diameter.
Bushy, low, 1°-4° high, the stems and often the branches, densely armed with straight prickles; infrastipular spines none. Stipules mostly broad; leaflets 5-9 (rarely 3), oval or oval-lanceolate, obtuse at the apex, rounded at the base, simply or doubly serrate, often more or less resinous-pubescent, 1'-2' long; flowers usually solitary, 2 1/2'-3' broad; calyx-lobes lanceolate, acuminate or sometimes dilated above, entire or few-toothed, persistent and erect upon the fruit; styles distinct; fruit globose or ovoid, sometimes X long, generally glabrous.
Anticosti to Ontario, Alaska, northern Michigan, Minnesota, south in the Rocky Mountains to Colorado. Northern Europe and Asia. Consists of several races, differing in the form of the fruit and in the amount of pubescence. June-July.