Copse Bindweed

A fairly common species, easily differentiated by its winged fruits and smaller nuts.

Because of similarity to Fallopia scandens, specimens of F. dumetorum often are misidentified. Consequently, the range of F. dumetorum in North America is unclear; it is probably exaggerated in most floras.

Mature fruiting perianths provide the most reliable characters distinguishing Fallopia dumetorum from F. scandens. European specimens of F. dumetorum, have fruiting perianths that are consistently orbiculate in outline, with wings usually flat and abruptly contracted on the stipelike perianth bases. Fallopia scandens has fruiting perianths that are obovate in outline, with wings undulate and gradually decurrent on the stipelike perianth bases. Additional characteristics reported to distinguish F. dumetorum from F. scandens are its annual habit (F. scandens also is reported to be annual in some of the literature) and more triangular leaf blades with cordate or sagittate bases. In recognizing F. dumetorum, we follow S. T. Kim et al. (2000) and M. H. Kim et al. (2000), who concluded from limited morphological and flavonoid data that the taxa are best treated as distinct species. More detailed studies may prove the two to be conspecific.

Herbs, annual, not rhizomatous, to 3 m. Stems scandent or climbing, rarely prostrate, freely branched, herbaceous, glabrous to papillose or scabrid, not glaucous. Leaves: ocrea usually deciduous, tan or brown, cylindric to funnelform, 1.5-3.5 mm, margins oblique, face not fringed with reflexed hairs and slender bristles at base, otherwise glabrous or scabrid; petiole 0.3-2.5 cm, glabrous or scabrid in lines; blade triangular to hastate, 2-8 × 1-5 cm, base cordate to truncate, margins wavy, scabrid, apex acute to acuminate, abaxially and adaxially faces glabrous or papillose to scabrid, not glaucous, the abaxial rarely minutely dotted. Inflorescences axillary, erect or spreading, racemelike, 2-20 cm, axes glabrous or scabrid; peduncle 0.1-6 cm or absent, glabrous or scabrid. Pedicels ascending or spreading to deflexed, articulated distally, 4-8 mm, glabrous. Flowers bisexual, 2-6 per ocreate fascicle; perianth accrescent in fruit, greenish white or pinkish, 3.5-7 mm including stipelike base, glabrous; tepals elliptic to obovate, apex obtuse to acute, outer 3 winged; stamens 8; filaments flattened proximally, pubescent proximally; styles connate; stigmas capitate. Achenes included, black, 2-4 × 1.8-2.4 mm, shiny, smooth; fruiting perianth glabrous, wings flat or, less often, undulate or crinkled, 1.5-2 mm wide, usually truncate or attenuate-decurrent on stipelike base nearly to articulation, margins entire or rarely undulate-crenate. 2n = 20.

Annual herbs, 50-200 cm long, twining, stem branched, smooth, angled. Leaves petiolate, petiole 5-30 mm long, blade 3-8 x 2-5 cm, ovate-cordate, acuminate, glabrous but somewhat puberulous on midribs, ochrea truncate, soon falling, 1-2 mm long. Flowers small, arranged in loose terminal racemes and also 2-5 flowered in axillary fascicles; pedicel 2-4 mm long, equalling the length of perianth, articulated below the middle. Bract small, elliptic to ovate. Perianth 5-cleft, outer 3, enlarging into coriaceous wings, along the midrib, 6-8 x 2-3 mm. Wings 1-1.5 mm broad, entire or toothed. Stamens 7-8 with short filaments and dorsifixed anthers. Ovary trigonous, styles short, stigmas capitate. Fruiting pedicel 6-8 mm long. Nut 2.5-3 mm long, black-dark brown, shining, faces concave.

Herbs annual. Stems twining, 70-150 cm, striate, papillate, glabrous, much branched. Petiole 1-3 cm, papillate; leaf blade ovate-cordate, 3-6 × 1.5-4 cm, both surfaces glabrous, along veins minutely papillate, base cordate or sagittate, margin entire, apex acuminate; ocrea short, 2-3 mm, membranous, oblique, apex acute, not ciliate. Inflorescence usually axillary, racemose, lax, few or many flowered; bracts 1.5-2 mm, membranous, each 1-6-flowered. Pedicel 3-4 mm, slender, articulate, elongate in fruit. Perianth greenish, 5-parted; tepals elliptic, 2-3 mm, unequal in size, outer 3 larger and winged in fruit; wings entire, slightly decurrent along pedicels. Perianth (including wings) in fruit orbicular, 4-4.5 mm in diam. Stamens 8, included. Styles very short; stigmas capitate. Achenes included in persistent perianth, black, shiny, ellipsoid, trigonous, 3-3.5 mm, smooth. Fl. Jun-Aug, fr. Jul-Sep.

Distribution: Europe, Mediterrenean region N. & West Asia and Temperate Himalyas.

Europe, W. Asia, Himalaya, N. America, often naturalised.

Hebei, Heilongjiang, Jiangsu, Jilin, Liaoning, Nei Mongol, Shandong, Xinjiang [Bhutan, N India, Japan, Korea, Mongolia, Nepal, Pakistan, Russia; SW Asia, Europe].

introduced; Ont., Que.; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Ky., La., Maine, Md., Mass., Mich., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Tex., Vt., Va., W.Va., Wis.; Europe; Asia.

2100 m

Fl. Per.: May-September.

Flowering Jul-Oct.

Grassy slopes, thickets and mixed forests in valleys, mountain valleys, fields; 200-2400 m.

Hedges, wood borders, fields, waste ground; 0-300m.

Grows on walls in moist and shady places between 1800-4500 m.

Polygonum dumetorum L., Sp. Pl. ed. 2: 522. 1762; Hook. f., Fl. Brit. Ind. 5: 24. 1886; Coode & Cullen in P.H.Davis, Fl. Turk. 2: 280. 1966; Schiman-Czeika & Rech.f., Fl. Iran. 56: 52. 1968; Kom., l.c. 695; R.R.Stewart, Ann. Cat. Vasc. Pl. W. Pak. & Kashm. 205. 1972; Bhopal & Chaudhri in Pak. Syst. 1(2): 70. 1977; Tinaria dumetora (L.) Nakai in Mori, Enum. Pl. Korea 136. 1922; Fagopyrum dumetorum (L.) Schreb. Spic. Fl. Lips. 42. 1771; Bilderdykia dumetorum (L.) Dumort., Fl. Belg. 18. 1827; D.A.Webb in Tutin et al., Fl. Europ. 1: 81. 1964; Munshi & Javeid, Syst. Stud. Polygon. Kashm. Himal. 81. 1986; Fagopyrum membranaceum Moench, Meth. 290. 1794.

Polygonum dumetorum Linnaeus, Sp. Pl. ed. 2, 1: 522. 1762; Bilderdykia scandens (Linnaeus) Greene var. dumetorum (Linnaeus) Dumortier; Polygonum scandens Linnaeus var. dumetorum (Linnaeus) Gleason; Reynoutria scandens (Linnaeus) Shinners var. dumetorum (Linnaeus) Shinners; Tiniaria dumetorum (Linnaeus) Opiz