Rosa omeiensis Rolfe

Four forms can be recognized: R. omeiensis f. omeiensis, which has leaflets abaxially pubescent to subglabrous and non-glandular; f. glandulosa T. T. Yü & T. C. Ku (Bull. Bot. Res., Harbin 1(4): 7. 1981), which has abaxially densely glandular leaflets; f. pteracantha Rehder & E. H. Wilson (in Sargent, Pl. Wilson. 2: 332. 1915), which has branches with purple, broad, flat, winglike prickles; and f. paucijuga T. T. Yü & T. C. Ku (Acta Phytotax. Sin. 18: 502. 1986), which has only 5–9 glabrous leaflets, slightly turgid fruiting pedicels, and is intermediate between R. omeiensis and R. sericea.

The root bark, which contains about 16% tannin, is used for tanning. The sweet, edible fruit are used medicinally and to ferment wine.

Shrubs erect, 1–4 m tall. Branchlets slender; prickles absent or if present, paired below leaves, terete, straight, to 7 mm, abruptly flaring to a broad base, or prickles winglike, to 1.5 cm and 3 cm in diam.; bristles absent or if present, dense. Leaves including petiole 3–6 cm; stipules mostly adnate to petiole, free parts triangular-ovate, margin serrate or entire, sometimes glandular; rachis and petiole with a few small prickles; leaflets (5–)9–13(–17), oblong or elliptic-oblong, 8–30 × 4–10 mm, abaxially glabrous or pubescent, glandular or not, adaxially glabrous, with concave midvein, base rounded-obtuse or broadly cuneate, margin acutely serrate, apex acute or rounded-obtuse. Flower solitary, axillary, 2.5–3.5 cm in diam.; pedicel 6–20 mm, glabrous; bracts absent. Hypanthium obovoid or pyriform, glabrous. Sepals 4, lanceolate, abaxially subglabrous, adaxially sparsely pubescent, margin entire, apex acuminate or long caudate. Petals 4, white, obtriangular-ovate, base broadly cuneate, apex emarginate. Styles free, shorter than stamens, villous. Hip bright to deep red or yellow, obovoid or pyriform, 8–15 mm in diam., glabrous or glandular-pubescent, with persistent, erect sepals; pedicel yellow, tapering to hip, 6–20 mm, stout, fleshy, glabrous. Fl. May–Jun, fr. Jul–Sep.

Gansu, Guizhou, Hubei, Ningxia, Qinghai, Shaanxi, Sichuan, Xizang, Yunnan.

Abies forests, thickets, scrub, pastures, hillsides, slopes; 700--4000 m.

Rosa sericea Lindley f. aculeatoeglandulosa Focke; R. sericea f. inermieglandulosa Focke; R. sorbus H. Léveillé.

Flowering from May to June; fruiting from July to September.

Rosa omeiensis is close relative of Rosa taronensis, but differs from the latter in its leaflets 9-17 (vs. 7-9), oblong or elliptic-oblong (vs. oblong or oblong-obovate), abaxially glabrous or puberulous along midvein (vs. glabrous, shortly bristly), margin serrate from base to apex (vs. near apex serrate), petals white (vs. yellowish), hip red or yellow (vs. orange-yellow), obovoid or pyriform (vs. obconic).

Rosa omeiensis is occurring in Gansu, Guizhou, Hubei, Ningxia, Qinghai, Shaanxi, Sichuan, Xizang, Yunnan of China.

Phylogenetic analyses of Rosa were inferred from non-coding chloroplast sequences trnL-F region and psbA-trnH (Bruneau et al., 2007). Bayesian and parsimony analyses suggest that subgenus Rosa can be divided into two large clades. One comprises species from sections Carolinae, Cinnamomeae and Pimpinellifoliae p.p., whilst the other consists of all of the remaining sections of subgenus Rosa (Banksianae p.p., Bracteatae, Caninae, Indicae, Laevigatae, Rosa, Synstylae and Pimpinellifoliae p.p.). A fairly complete sampling of field-collected North American taxa has been incorporated in this analysis. Analyses indicate that migration into North America occurred at least twice within this primarily Old World genus. Most North American taxa, except R. setigera and R. minutifolia, fall into a single clade that includes Asian and European taxa. Analyses also are consistent with the notion that cultivated commercial roses have a relatively narrow genetic background. Six of the seven primary taxa believed to be involved in the creation of domesticated roses are found within the same large clade that mostly includes Asian and European taxa.

Shrubs erect, 1-4 m tall. Branchlets slender; prickles absent or if present, paired below leaves, terete, straight, to 7 mm, abruptly flaring to a broad base, or prickles winglike, to 1.5 cm and 3 cm in diameter; bristles absent or if present, dense. Leaves including petiole 3-6 cm; stipules mostly adnate to petiole, free parts triangular-ovate, margin serrate or entire, sometimes glandular; rachis and petiole with a few small prickles; leaflets 9-15, oblong or elliptic-oblong, 8-30 mm long, 4-10 mm wide, abaxially glabrous or pubescent, glandular or not, adaxially glabrous, with concave midvein, base rounded-obtuse or broadly cuneate, margin acutely serrate, apex acute or rounded-obtuse. Flower solitary, axillary, 2.5-3.5 cm in diameter; pedicel 6-20 mm, glabrous; bracts absent. Hypanthium obovoid or pyriform, glabrous. Sepals 4, lanceolate, abaxially subglabrous, adaxially sparsely pubescent, margin entire, apex acuminate or long caudate. Petals 4, white, obtriangular-ovate, base broadly cuneate, apex emarginate. Styles free, shorter than stamens, villous. Hip bright to deep red or yellow, obovoid or pyriform, 8-15 mm in diameter, glabrous or glandular-pubescent, with persistent, erect sepals; pedicel yellow, tapering to hip, 6-20 mm, stout, fleshy, glabrous.

Growing in Abies forests, thickets, scrub, pastures, hillsides, slopes; 700-4000 m.

The root bark of Rosa omeiensis, which contains about 16% tannin, is used for tanning. The sweet, edible fruit are used medicinally and to ferment wine.

Rosa omeiensis is a species of Rosa native to central and southwestern China in the provinces of Gansu, Guizhou, Hubei, Ningxia, Qinghai, Shaanxi, Sichuan, Xizang, and Yunnan; it grows in mountains at altitudes of 700 to 4,400 m.

It is a shrub which grows 4 m tall, and is often very spiny. The leaves are deciduous, 3–6 cm long, with 5–13 leaflets with a serrated margin. The flowers are 2.5–3.5 cm diameter, white, with (unusually for a rose) only four petals. The hips are red to orange-yellow, 8–15 mm diameter, with persistent sepals, and often bristly.

There are four formae:

Rosa omeiensis f. omeiensis. Rosa omeiensis f. glandulosa T.T.Yü & T.C.Ku. Rosa omeiensis f. paucijuga T.T.Yü & T.C.Ku. Rosa omeiensis f. pteracantha Rehder & E.H.Wilson.

It is sometimes treated as a subspecies of the closely related species Rosa sericea.