Vigorous, colony-forming shrub to 3 m tall Stem: arching, climbing, or trailing, with recurved prickles. Leaves: pinnately compound, stalked, with five to eleven (usually seven or nine) leaflets. The leaflets are 2 - 4 cm long, elliptic to inversely egg-shaped with a blunt to pointed tip, toothed, and hairy. Flowers: borne on a many-flowered pyramidal inflorescence, 2 - 4 cm across, with non-persistent sepals 5 - 8 mm long that usually have a tail-like tip and some slender lobes, white (rarely pink) petals 1 - 2 cm long, and stamens and styles (united and hairless) exserted 1. 5- 3 mm. Fruit: bony achenes surrounded by the mature floral tube (hip). The hip is red, to 8 mm long, and nearly spherical. Stipules: subtending leaves, fringed-toothed and glandular-hairy along margins.
Similar species: Both Rosa multiflora and Rosa setigera have a climbing or trailing habit and flowers with united, protruding styles. Rosa setigera differs by its three or five leaflets and its pink flowers.
Flowering: late May to late June
Habitat and ecology: Introduced from Asia, this species used to be planted as a hedge. It has escaped and become an invasive weed of degraded areas.
Occurence in the Chicago region: non-native
Etymology: Rosa is the Latin name for a rose. Multiflora means many-flowered.
Vigorously colonial; stems climbing or scrambling to 3 m; stipules conspicuously pectinate-serrate and glandular-ciliate; lfls 5-11, to 2.5 cm, elliptic to obovate; infl many-fld; sep often caudate-tipped, often with some slender lateral lobes, eventually deciduous; pet white (pink) 1-1.5(-2) cm; styles connate, exserted 1.5-3 mm, glabrous; 2n=14. Native of e. Asia, often escaped from cult.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.