F.C. Stern A Study of the Genus Paeonia

4. P.lutea Delavay ex Franchet in Bull. Soc. Bot. France, 33, 382 (1886), et PI. Delavay. 32 (1889) ; Huth in Engl. Bot, Jahrb. 14, 272 (1892) ; Journ. Soc. Nat. Hort. France, Ser. 3, 15, 274 (1893) ; Jardin, 11, 216, cum tab. (1897) ; Bot. Mag. t. 7788 (1901) ; Flora and Sylva, 1, 230, 231 cum tab. et fig. (1903) ; Rev. Hort. Beige, 29, 177, fig. 26 (1903) ; Raffill in Gard. Chron., Ser. 3, 35, 372 (1904) ; Garden, 76, 416, cum fig. (1912), 84, 352, cum fig. (1920) ; Harding, Peony, 113, cum tab. (1917) ; Bean, Trees and Shrubs, Ed. 3, 2, i2i (1921) ; Rehder, Man. Cult. Trees and Shrubs, 215 (1927) ; Handel-Mazzetti, Symb. Sinicae, 7, 266 (1931) ; Saunders in Nat. Hort. Mag. 13, tab. pP.222, 223 (1934) ; F.C. Stem in Journ. Roy. Hort. Soc. 68, 125 (1943).Syn. P.lutea var. superba Hort. ex Gard. Chron., Ser. 3, 44, 50, cum tab. (1908).P.Delavayi Franch. var. lutea (Franch.) Finet & Gagnepain in Bull. Soc. Bot. France, 51, 524 (1904), et Contrib. Ft. Asie Or. 221 (1905) ; Lemoine in Rev. Hort., 1906, P.14, cum tab. ; Schipczinsky in Not. Syst. Herb. Hort. Bot. PetroP.2, 47 (1921) ; Marquand in Journ. Linn. Soc. London, Bot. 48, 158 (1929).P.Delavayi var. lutea forma superba Lemoine in Rev. Hort., 1906, P.14, cum tab.

Description. A shrub up to 1-5 m. high, quite glabrous. Leaves bitemate ; petioles 8-14 cm. long ; terminal set of leaflets borne on a common petiolule 4-5 cm. long, lateral sets of leaflets with common petiolule 2-2 -5 cm. (rarely 3-5 cm.) long ; leaflets incisely lobed and toothed but not greatly dissected, the lobes and teeth not much spreading, acute with the apex blunt, dark green above, glaucous beneath ; terminal leaflet (of each set) about 10 cm. long, deeply 3-sect, the middle segment about 3 cm. wide and shortly 3-4 lobed, the lateral segments oblong-acute, entire or with i or 2 teeth near the apex, i •2-1 •'} cm. wide ; lateral leaflets of the terminal set 8-9-5 cm. long, about 3 cm. wide, shortly 3-5 lobed, those of lateral sets 4'7-8-5 cm. long, i -7-2-7 cm. wide, 1-3 toothed to deeply segmented and 3-4 lobed or toothed. Flower 5-6 cm. across (in cultivation to 7 cm.). Bracts and Sepals together (5-8), persistent, the outer 3-4 narrow-oblong to narrow elliptic, acute, 2-7 cm. long by 3-8 mm. wide, foliaceous ; the intermediate ones oblate and caudate to suborbicular and cuspidate, about 2 cm. long (including apex) and i -5 cm. wide ; the inner suborbicular, shortly cuspidate to rounded, i -5-1 -8 cm. long, thinly leathery, greenish, often flushed with red and with a thin, whitish margin. Petals yellow, obovate from a cuneate base, rounded 2-5-3-5 cm. long by 2-2-5 cm. wide, somewhat concave. Stamens yellow, r2-i'5 cm. long. Carpels glabrous, conical, shortly attenuated to the very small flattened circular stigma, n-i cm. long (1-4 cm. in cultivation). Disc produced as conspicuous fleshy lobes 3-4 cm. high round the base of the carpels. Follicles 3 cm. long, i -5 cm. wide.

Distribution. china : Yunnan, Mt. Hea Chan Men, 1883, Delavay (K) ; Mt. Che-tcho-tze, above Ta-pin-tze, Delavay (K) ; Lankong, Delavay (P) ; Mekong-Salween Divide, Tali Range, Forrest (E) ; Lang-Kong-Hoching Divide, Forrest (E) ; Pe-Lang-Tsin, 3200 metres, Maire (P) ; Chungtien, 11,500 ft., Rock (E) ; Likiang, 11,000 ft., Rock (E) ; Mekong-Yangtse Divide, Rock (E) ; Tan-Tui, descent to Yangtse, 11,000 ft., K. Ward (E) ; Szechwan, Forrest (E) ; Legendre igis (P). tibet : Lung Chayal, 9500 ft., Ludlow & Sherriff, No. 1376 (BM) ; Kyari Dzong Pashu E, 12,500 ft., Hanbury-Tracy, 200 (BM) ; Tsela-Dzong in the Tsangpo, K. Ward 5691 (K) ; Chayal Dzong on the Loro River, K. Ward (BM).

Paeonia lutea is a yellow-flowered, shrubby paeony which differs from P.Delavayi in its yellow flowers and in the absence of the involucre below the calyx which is so characteristic of P.Delavayi, and in having only one to four foliaceous bracts.

It is very variable in its habit of growth ; some specimens being taller than others with their flowers showing above the foliage, while others form bushes with the flowers hidden among the leaves. Some American botanists have considered it to be merely a variety of P.Delavayi, but in view of the differences between the two plants, which are to be seen in all the specimens examined, the specific rank ascribed to it by Franchet (1886) has been maintained, though no doubt in a wild state it crosses freely with the other species in the group.

This species was discovered by Pere Delavay in Yunnan in 1883. His original specimens, on which he wrote the name P.lutea, are in the herbarium of the Musee nationale d'Histoire [end page 046] naturelle, Paris, and it was described under that name by Franchet in 1886. Delavay notes about one of his specimens that the petals were red or purple at the base. Dr. Legendre, who collected the plant in Szechwan in 1912, also refers to the purple stain at the base of the petal. The leaves vary considerably in breadth and length in plants from different districts ; a specimen from eastern Tibet in the British Museum has very narrow leaflets and the base of the petals is red. Kingdon Ward mentions a plant he saw in Tibet 6 to 8 ft. high. The collectors report P.lutea as growing usually from i m. to i^ m. high in spruce forests between 11,000 and 13,000 ft. The distribution seems to be from the Likiang Range north slightly westwards along the Mekong-Yangtse Divide and Mekong-Salween Divide into eastern Tibet as far as Tsela-Dzong on the Tsangpo River.

Kingdon Ward informs me that P.lutea has only so far been found in Tibet in three or four localities in or near the Tsangpo Valley ; he thinks the plants may have been introduced by caravans coming from China and that it has subsequently naturalised itself in those localities.

This paeony is an accommodating and perfectly hardy plant in cultivation and grows well in any good soil and in any situation. It has been used with great success by Messrs. Lemoine of Nancy and Professor A. P.Saunders of Clinton College, New York, as the seed parent crossed with cultivated forms of P.suffruticosa and has produced some fine yellow-flowered hybrids. The best known of these hybrids are P.X " Argosy " and P.X " Esperance." [end page 047]