Rosa davidii (Species)

Curtis's Botanical Magazine (1916) v. 142, Ser. 4 no. 12, tab 8679.
TAB. 8679
ROSA DAVIDII
China
ROSACEAE. Tribe ROSEAE
ROSA, Linn.; Benth. et Hook. f. Gen. Plant. vol. i. p. 625.

Fig. 1, a flower in vertical section, the petals removed; 2 and 3, anthers; 4, carpel with style; 5, achene:—all enlarged.

Rosa Davidii, Crép. in Bull. Soc. Bot. Belg. vol. xiii. p. 253 (1874); Franch  in Nouv. Arch. Mus. Paris, sér. 2, vol. v. p. 270 (Pl. David. vol. i. p. 118) Rehder Wils. in Sarg. Pl. Wilson. vol. ii. p. 332; affinis R. corymbulosae, Rolfe, sed foliolis plurimis simpliciter serratis, corymbis laxis, bracteis majoribus, floribus majoribus et glandulis longioribus differt.

Frutex  erectus, parce ramosus, 1-2-metralis; ramuli laeves, aculeis rectis patentibus sublatis dispersis 4-6 mm. longis armati, demum brunnoi. Folia 8-10 cm. longa, 7-9-foliolata; rhachis puberula, aculeis gracilibus  sparsis instructa;  foliola subsessilia, elliptico-oblonga vel ovato-oblonga, subacuta, simpliciter et acute serrata, subtus cinereo-puberula, 2-3 cm. longa, 1-1.5 cm. lata; stipulae adnatae, anguste oblongae, acutae vel acuminatae, integrae, 0.7-1.5 cm. longae. Flores rosei, corymbulosi, versus apices ramorum laxe dispositi, circiter 3 cm. diametro. Bracteae  ovatae, acuminatae, puberulae, 1.2-1.5 em. longae. Pedunculi graciles, 3-4 cm. longi, glanduloso-setulosi. Receptaculum anguste ovoideo-oblongum, 3-4 mm. longum, crebre glandulosum. Calycis lobi basi ovati, apice longe foliacei et lanceolati, acuti, 1.3-2 cm. longi, patentes, intus cinereo-tomentosi. Petala late obcordata. Filamenta glabra, 4-5 min. longa;   antheris aureis. Styli villosi, in columnam 6 mm. longam cohaerentes. Fructus ovoideus, 1-1.3 cm. longus, coccineus, sepalis persistentibus suberectis coronatus. Achaenia villosa, ovoidea, 3 mm. longa.—R. A. ROLFE.

The Rose here figured was originally described by Crépin in 1874, and was based on a flowering specimen forwarded by Decaisne which was then believed to have been received through the Abbé David from Mongolia. It was placed somewhat doubtfully in the section Synstylae, and was compared with R. moschata, Herrm., though the difference in colour of petals and in the shape of the sepals and bracts was pointed out. This comparison and the reference to Synstylae have tended to obscure the identity of David's plant, but a photograph of the original specimen supplied by Mr. Gagnepain shows that on the original label Crépin added to the name the remark "R. macrophylla, var.," a suggestion more in accord with its true affinity. This photograph further shows that David had himself given the locality as Eastern Tibet, and Mr. E. H. Wilson, who has also collected this species, remarks that it is common on the mountains of Moupine in Western Szechuan. The bush from which our plate has been prepared was raised from seed sent from the Arnold Arboretum in 1909. At Kew it has grown very freely and borne good crops of its graceful fruit. The seed in question was obtained by Wilson in September, 1908, near Wen-ch'uan Hsien in Western Szechuan at 7,000-10,000 feet above sea-level. In the wild state it occurs in thickets and forms a bush three to five feet in height. At Kew it has proved one of the most easily grown species of Rose, and thrives excellently in stiff loamy soil. In addition to the highly coloured fruits a marked feature of this Rosa is afforded by the numerous ovate bracts which sometimes exceed in size those shown in our figure. Like other members of its group, R. Davidii should be easily increased by cuttings taken in August and placed in a propagating case in gentle heat.

DESCRIPTION.Shrub, sparingly branched, 3-5 ft. high; twigs smooth, armed with straight, spreading, subulate, scattered prickles 1/8-1/6 in. long, bark at length brown. Leaves 3-4 in. long, 7-9 foliolate; rachis puberulous, with scattered slender prickles; leaflets subsessile, elliptic-oblong or ovate-oblong, subacute, simply sharply serrate, grey puberulous beneath, 3/4-1 1/4 in. long, in. wide; stipules adnate, narrow-oblong, acute or acuminate, entire, in. long.  Flowers rose-pink, somewhat loosely corymbose, near the tips of twigs, about 1 1/4 in. across; bracts ovate, acuminate, puberulous, 1/2 -2/3 in. long; peduncles slender, 1 1/4-1 1/2  in long, slender, setose. Receptacle narrowly ovoid-oblong, 1 1/4-1 1/2 in. long, closely glandular. Calyx-lobes leafy, lanceolate from an ovate base, acute, 1/2-3/4 in. long, spreading, grey-tomentose within. Petals wide-obcordate. Filaments glabrous, 1/6-1/5 in. long; anthers golden-yellow. Styles villous, cohering in a column 1/4 in. long. Fruit ovoid, 1/3-1/2 in. long, pink, crowned by the persistent suberect sepals. Achenes villous, ovoid, 1/8 in. long.