POLYGONUM 



POLYGONUM 



2741 



Asian set, from elevations in the Himalayan region and 

 eastward to China and Japan, comprises very inter- 

 esting plants for rock-gardens and herbaries. The 

 polygonums provide good autumn-blooming plants. 



INDEX. 



able plant for backgrounds: glabrous or nearly so, ereet 

 or somewhat diffuse, 1-2 ft. tall: Ivs. lanceolate to 

 linear-lanceolate, slightly ciliate, usually with a trian- 

 gular or crescent-shaped spot near the middle of the 

 blade (whence the name lady's thumb) ; sheaths short, 

 hairy on the margin: fls. in short spikes, pink or green- 

 ish purple, the stamens 6 and the achene lenticular 

 or triquetrous. Eu. Naturalized everywhere about 

 dwellings. 



6. arenarium, Waldst. & Kit. (P. elegans, Ten.). 

 Dwarf annual species with slender wiry branches and 

 long internodes: Ivs. small, linear-lanceolate, 1-nerved, 

 bearing great numbers of little whitish fls. along the St., 

 the terminal clusters leafless. S. Eu. Offered in Calif, 

 for rockeries and bouquets. 



A. Habit twining. 



1. cilindde, Michx. Slender somewhat downy 

 cumber, mostly perennial: Ivs. cordate-ovate to 

 ovate-lanceolate, more or less angular or halberd- 

 shaped at base: st. bearing a ring of retrorse bristles 

 at the base of each sheath (whence the specific 

 name): fls. white, in loose-panicled racemes from 

 the upper axils. Nova Scotia south and west. R.H. 

 1913, p. 149. Sold as a cover-plant for rocks and as a 

 denizen of shrub-masses. 



2. baldschuanicum, Regel. Fig. 3103. Tall perennial 

 climber becoming woody at the base: Ivs. cordate-oval 

 or hastate, acuminate, slender-petioled: fls. small but 

 very numerous, in terminal erect or drooping panicles, 

 mostly rose-colored; fruiting calyx small, 3-sided, at first 

 whitish and then becoming rose-colored: achene shi- 

 ning black. Bokhara. B.M. 7.544. R.H. 1900, p. 35. 

 Gt. 52, p. 381. G.C. III. 21:17; 41:399. Gn. 55, p. 

 454; 70, p. 274; 71, p. 19; 79, p. 41. G.M. 50:310. G. 

 35:657. G.W. 4, p. 253; 15, p. 626. Gng. 5:181 A 

 very vigorous and decorative hardy plant, climbing 20 

 ft. high, and, under favorable conditions, producing a 

 profusion of pinkish, or sometimes whitish bloom ; hardy 

 N., and worthy greater attention. It was first described 

 by Regel in 1884; bears the name of the town or place 

 Baldschuan. 



3. Aubertii, Henry. Resembles P. baldschuanicum., 

 but said to be inferior to it : climbing to 25 ft. and more, 

 becoming woody at base : Ivs. ovate-lanceolate, cordate, 

 obtuse or very short-pointed, reddish bronze or pale 

 green and when young red at the apex: fls. small, 

 whitish, rose-colored or green, in slender axillary 

 panicles 6-8 in. long. W. China, Thibet, discovered by 

 P. Georges Aubert, missionary. R.H. 1907, pp. 82, 83. 

 Said to grow with great rapidity, and to cover a 

 large space; blooms in spring and again in autumn. 



AA. Habit erect, or at least not dimbing. 

 B. Plants annual, of erect habit, to be treated as flower- 

 garden subjects. 



4. orientale, Linn. (Persicaria orientalis, Spach). 

 PRINCE'S FEATHER. Fig. 3104. Tall-growing annual, 

 much branched above, hairy: Ivs. large, ovate or cor- 

 date-ovate or broad-oblong, acuminate; sheaths short, 

 ciliate and sometimes bordered at the summit : fls. bright 

 pink, in close, cylindrical spikes that are arranged in 

 open panicles, the stamens 7 and the achene lenticular. 

 India. B.M. 213. J.H. III. 51:305. G.W. 6, p. 148 

 An attractive old-fashioned plant growing as high as 

 the fence. It is most easy of cult.; in fact, it usually 

 self-sows in old gardens. In some places it has run wild. 

 There are horticultural varieties, as var. variegatum, 

 Hort., with foliage marked with yellowish white, and 

 var. pumilum, Hort., with compact habit and the 

 stature half that of the type. 



5. Persicaria, Linn. LADY'S THUMB. One of the 

 annual smartweeds, but sold by seedsmen as a suit- 



3104 Polygonum orientale. ( X }4) 



BB. Plants perennial, of various habit, usually with strong 



rootstocks, sometimes shrubby. 



c. Species native: smartweed-like plants, sometimes offered 

 for naturalizing in bog-gardens. 



7. amphibium, Linn. (Persicaria amphibia, S. F. 

 Gray). Much spreading and creeping, rooting at the 

 joints, at first more or less pubescent but becoming 

 glabrous with age : Ivs. rather thickish and large, oblong, 

 elliptic or lance-elliptic, mostly obtuse or very nearly so ; 

 sheaths short, usually not fringed or bordered at the 

 summit: fls. light rose-colored, in a short, dense, 

 terminal spike, the stamens 5 and exserted, and the 

 achene lenticular. In water or bogs, across the con- 

 tinent, and useful for planting in similar places. 

 When growing in water, the floating Ivs. become long- 

 petioled. Var. Harrwrightii, Bissefl (P. Hartwrightii, 

 Gray). Differs from the last in having many narrow- 

 lanceolate Ivs., bordered and fringed sheaths, and hispid 

 sts., but the distinguishing mark is the foliaceous border 

 on the sheath. Muddy places, across the continent. 



cc. Species exotic, used mostly for borders, and appearing 

 regularly in the trade, largely Himalayan and E. 

 Asian. 



D. Whole plant white-woolly. 



8. lanigerum, R. Br. Sts. thick, creeping at the 

 base, but the tops erect and standing 2-5 ft. high, much 

 branched: Ivs. narrow-lanceolate and more or less 



