Shrub to 3.5 m tall Stem: arching, highly branched, with uniform, lance-shaped, recurved prickles to 1 cm long, lacking bristles. Leaves: pinnately compound, stalked, with five to seven leaflets. The leaflets are 1.5 - 3 cm long, broad egg-shaped to oval with a pointed tip, gland-toothed, hairless or hairy and sparsely glandular above, hairy and glandular beneath, and slightly aromatic. Flowers: one to four per cluster, 2 - 3 cm across, with a glandular hairy stalk, non-persistent and hairless sepals that are usually pinnately lobed, pale pink to white petals, and hairless styles that are shortly exserted. Fruit: bony achenes surrounded by the mature floral tube (hip). The hip is scarlet to orange and egg-shaped to nearly spherical.
Similar species: Rosa canina, Rosa eglanteria, and Rosa micrantha have stout, recurved prickles and small clusters of flowers with shorty exserted styles and often pinnately lobed sepals. Rosa canina differs by having non-aromatic, glandless, egg-shaped to elliptic leaflets. Rosa eglanteria is distinguished by its strongly aromatic, glandular-toothed, blunt-tipped, nearly rounded to broadly elliptic leaflets that are glandular on both sides, and flowers with hairy styles and persistent sepals.
Flowering: June to July
Habitat and ecology: Introduced from Europe, this species rarely escapes in the Chicago Region, but commonly escapes elsewhere in the United States.
Occurence in the Chicago region: non-native
Etymology: Rosa is the Latin name for a rose. Micrantha means small-flowered.