1392 



POLYGONATUM 



DD. Filaments somewhat flattened, smooth, not 



roughened. 



giganteum, Dietr. Taller and more robust than P. 

 biflorum, 1-8 ft. high: Ivs. 1^-6 in. long, 3-4 in. wide: 

 fls. 1-8 in the axils. May-July. Moist woods, Rhode 

 Island to Manitoba, south Ga., La., to New Mex. and 

 Utah. 



CO. Plant with Ivs. pubescent beneath. 

 bifldnun, Ell. Height 8 in.-3 ft. : Ivs. 2-4 in. long, 

 ^-2 in. wide: fls. often 2 in axils, sometimes 1-4. 

 April-July. Woods, New Brunswick to Mich., south to 

 Fla. Mn. 8:49. W. M. 



POLYGONELLA (diminutive of Polygonum). Poly- 

 gonacece. About 7 species of American plants closely 

 allied to Polygonum and of no horticultural 

 standing. P. parvi folia was offered by Gil- 

 lett in 1881, but it is probably not hardy 

 north. The genus differs from Polygonum 

 in having only the inner sepals erect and 

 the calyx enlarged in fruit, while in Poly- 

 gonum all the sepals are erect and the calyx 

 is not enlarged in fruit. 



parvifdlia, Michx. Diffuse shrub : 

 Ivs. wedge-shaped, vertical, those 

 on sterile shoots imbricated: ra- 

 cemes %-l in. long, very numerous, 

 in an oblong or corymbose panicle: 

 fls. white, yellowish or rose color; 

 filaments all alike; stigmas nearly 

 sessile. Aug., Sept. Dry sandy 

 soil, Pla. to N. C. 



1877. Common Doorweed or Knotweed, the details enlarged 

 Polygonum aviculare. 



POLYGONUM (Greek for many -jointed). Polygo- 

 nacecB. JOINTWEED. KNOTWEED. Mostly herbs, annual 

 or perennial, with small flowers in racemes, spikes or 

 heads (sometimes solitary). Flowers apetalous; calyx 

 gamosepalous, 4-5-parted; stamens 5-9, sometimes ex- 

 serted: ovary 1-loculed, with 2-3-parted style or stigma 

 (latter capitate), ripening into a triangular or 

 lenticular akene. Above each joint, the stem is 

 prominently sheathed. Polygonum is closely 

 allied to Rumex, the docks, and also to Fago- 

 pyrum, the buckwheats. Rumex differs in uni- 

 formly having a 6-parted calyx, some of the 

 lobes often bearing a grain-like tubercle on the 

 back, the stigmas tufted. Fagopyrum differs in having 

 an akene surpassing the calyx and in details of the 

 embryo. Most Polygonums are weedy plants, and only 

 a very small proportion are of merit for cultivation. 

 One of the commonest species is the Doorweed (Fig. 

 1877), Polygonum aviculare. It is a decumbent wiry 

 small-leaved annual or perennial, growing along walks 

 and in other hard, dry soil, where it makes a sod-like 

 mat. The axillary flowers are very small, and seldom 

 seen by others than botanists. Other Polygonums are 

 the common Smartweeds of swales and damp grounds. 

 For monograph of Polygonum, see Meisner, DC. Prodr. 

 14 (1856). For our native and introduced species, see 

 Small, "Monograph of the North American species of 

 the genus Polygonum," in Mem. Dept. Bot. Columbia 

 College, 1895. The species are perhaps 200, of very 

 wide distribution from arctic to tropical countries. 



Most of the cultivated Polygonums are hardy border 

 plants, requiring no special skill or care. They are prop- 

 agated by seed and division, chiefly the latter. Some 

 of the cultivated kinds are annual, as P. orientale, and 

 this species is the only one that is known as a familiar 

 flower-garden plant in this country. Several of the 

 species are amphibious and are quite useful for bog 

 gardens. 



A. Plant twining. 



1. cilinode, Michx. Slender somewhat downy climber, 

 mostly perennial: Ivs. cordate-ovate to ovate-lanceolate, 

 more or less angular or halberd-shaped at base: stem 

 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. Sold as a cover plant for rocks and as 

 a denizen of shrub-masses. 



2. Baldschuanicum, Regel. Tall perennial climber be- 

 coming woody at the base: Ivs. cordate-oval or hastate, 

 acuminate, slender-petioled: fls. small but very numer- 

 ous in terminal erect or drooping panicles, rose-colored: 

 fruiting calyx small, 3-sided, at first whitish and then 

 becoming rose-colored: akene shining black. Bokhara. 

 G.C.III.16:656; 21:17. Gn. 55, p. 454. Gng. 5:181. B.M. 

 7544. Offered by one American dealer and listed in 

 the American catalogues of European dealers. De- 

 scribed as a very vigorous and decorative hardy plant, 

 climbing 20 ft. high. It was first described by Regel 

 in 1884. 



AA. Plant erect, or at least not climbing. 



B. Annual plants of erect habit, to be treated as flower- 

 garden subjects. 



3. orientale, Linn. PRINCE'S FEATHER. KISS-ME- 

 OVER-THE-QARDEN-GATE, Fig. 1878. Tall-growing, much 

 branched above, hairy : Ivs. large, ovate or cordate- 

 ovate or broad-oblong, acuminate: sheaths short, cili- 

 ate and sometimes bordered at the summit: fls. bright 

 pink, in close, cylindrical spikes that are arranged in 

 open panicles, the stamens 7 and the akene lenticular. 

 India. B.M. 213. An attractive old-fashioned plant 

 growing as high as the fence. It is most easy of culti- 

 vation. In fact, it usually self-sows in old gardens. In 

 some places it has run wild. There are horticultural 



1878. Polygonum orientale (X M) 



