Rosa sect. Pimpinellifoliae
Mus. Helv. Bot. 1: 3. 1818.
Subshrubs, forming dense patches; rhizomatous, rhizomes long. Stems erect, 2–10(–15) dm; distal branches glabrous, eglandular; infrastipular prickles absent, internodal prickles erect or ± curved, usually intermixed with aciculi. Leaves persistent, 2.5–8 cm, membranous; stipules persistent, adnate to petiole, auricles flared, margins entire or serrate, eglandular or glandular; leaflets (5–)9–11(–13), terminal: petiolule 2–4 mm, blade oblong-ovate, suborbiculate, or broadly elliptic, 5–22 × 5–12 mm, abaxial surfaces glabrous, eglandular, adaxial green, dull, glabrous. Inflorescences: flowers solitary. Pedicels erect, slender, 15–35 mm, glabrescent, eglandular, sometimes with aciculi; bracts absent. Flowers 2–4 cm diam.; hypanthium subglobose, glabrous, eglandular; sepals persistent, erect, ovate-lanceolate, 10–12 × 2.5–3 mm, margins entire, abaxial surfaces glabrous, eglandular; petals single, white [rarely pink]; carpels 18–23, styles free, lanate, stylar orifice 2.5–3 mm diam., hypanthial disc flat, 4–4.5 mm diam. Hips blackish purple, globose or subglobose, 8–13 × 8–16 mm, lustrous, glabrous, eglandular; sepals persistent, erect. Achenes basiparietal.
Distribution
Introduced; Eurasia, introduced also in Atlantic Islands (Iceland), Pacific Islands (New Zealand).
Discussion
Species ca. 25 (1 in the flora).
In addition to the species treated here, yellow-flowered Rosa hugonis Hemsley has been reported from Ontario.
Selected References
None.