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bristly lady's-thumb, oriental lady's thumb, oriental lady's-thumb smartweed

r enouée robuste, stout dotted smartweed, stout smartweed

Habit Plants annual, 3–8 dm; roots also often arising from proximal nodes; rhizomes and stolons absent. Plants perennial, 3–20 dm; roots also sometimes arising from proximal nodes; rhizomes present, stolons sometimes present.
Stems

decumbent to ascending, branched, without noticeable ribs, glabrous.

ascending, usually branched proximally, scarcely ribbed, glabrous, glandular-punctate;

branches sometimes creeping and rooting at nodes.

Leaves

ocrea hyaline to brownish, cylindric, 5–12 mm, chartaceous, base sometimes inflated, margins truncate, ciliate with bristles 4–12 mm, surface glabrous or strigose, not glandular-punctate;

petiole 0.1–0.3(–0.6) cm, glabrous, leaves sometimes sessile;

blade without dark triangular or lunate blotch adaxially, ovate-lanceolate to linear-lanceolate, 2–8 × 1–3 cm, base tapering to cuneate, margins antrorsely strigose, apex acute to acuminate, faces glabrous or sparingly strigose along veins abaxially, glabrous or strigose along midvein and margins adaxially, not glandular-punctate.

ocrea light brown, cylindric, 10–15 mm, chartaceous, base inflated, margins truncate, ciliate with bristles 3–12 mm, surface strigose, glandular-punctate;

petiole 0.2–2 cm, glandular-punctate;

blade without dark triangular or lunate blotch adaxially, lanceolate to elliptic-lanceolate, 4–20 × 2–4.5 cm, base tapered, margins antrorsely strigose, apex acute to acuminate, faces glabrous or main veins scabrous, glandular-punctate.

Inflorescences

terminal, sometimes also axillary, erect, uninterrupted, 10–40(–80) × 3–7 mm;

peduncle 10–50 mm, glabrous;

ocreolae overlapping, margins ciliate with bristles (0.5–)1–4(–6) mm.

terminal and axillary, erect, uninterrupted, 20–80 × 5–10 mm;

peduncle 5–40 mm, glandular-punctate;

ocreolae usually overlapping, margins eciliate or proximal ones sometimes ciliate with bristles to 1 mm.

Pedicels

ascending, 1–2 mm.

ascending to spreading, 2–5 mm.

Flowers

1–5 per ocreate fascicle, homostylous;

perianth pinkish green proximally, roseate distally, glabrous, not glandular-punctate, scarcely accrescent;

tepals 5, connate ca. 1/3 their length, obovate, 2.2–2.8 mm, veins not prominent, not anchor-shaped, margins entire, apex obtuse to rounded;

stamens 5, included;

anthers yellow, elliptic to ovate;

styles 3, connate proximally.

2–4 per ocreate fascicle, homostylous;

perianth greenish proximally, white distally, glandular-punctate with punctae ± uniformly distributed, slightly accrescent;

tepals 5, connate ca.1/3 their length, obovate, 3.2–4.2 mm, veins prominent or not, not anchor-shaped, margins entire, apex obtuse to rounded;

stamens 6–8, included;

anthers pink or red, elliptic;

styles 3, connate proximally.

Achenes

included, dark brown to black, 3-gonous, 1.6–2.3 × 1.1–1.6 mm, shiny, smooth.

included or apex exserted, dark brown to brownish black, 3-gonous, 2.7–3.6 × 2–2.5 mm, shiny, smooth.

Persicaria longiseta

Persicaria robustior

Phenology Flowering May–Oct. Flowering Jul–Oct.
Habitat Floodplain forests and woodlands, shorelines of ponds, moist roadsides, waste places Peaty shores, often in water on coastal plain or near coast
Elevation 0-300 m (0-1000 ft) 0-1500 m (0-4900 ft)
Distribution
from FNA
AL; CT; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NJ; NY; OH; PA; SC; TN; TX; VA; VT; WI; WV; BC; NB; ON; e Asia [Introduced in North America; introduced also in Europe]
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; DE; FL; IN; KY; MA; MD; ME; MI; MO; NH; NJ; NY; OH; PA; RI; TX; VA; NS; ON; QC; Central America; South America; West Indies
[WildflowerSearch map]
[BONAP county map]
Discussion

Persicaria longiseta is morphologically similar to another Asian species, P. posumbu (Buchanan-Hamilton ex D. Don) H. Gross (= P. caespitosa). Its spread in the United States since its introduction near Philadelphia in 1910 was summarized by A. K. Paterson (2000).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Persicaria robustior often is synonymized with P. punctata.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 5, p. 592. FNA vol. 5, p. 584.
Parent taxa Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Persicaria Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Persicaria
Sibling taxa
P. amphibia, P. arifolia, P. bicornis, P. bungeana, P. capitata, P. careyi, P. chinensis, P. glabra, P. hirsuta, P. hydropiper, P. hydropiperoides, P. lapathifolia, P. maculosa, P. meisneriana, P. minor, P. nepalensis, P. orientalis, P. pensylvanica, P. perfoliata, P. punctata, P. robustior, P. sagittata, P. setacea, P. virginiana, P. wallichii
P. amphibia, P. arifolia, P. bicornis, P. bungeana, P. capitata, P. careyi, P. chinensis, P. glabra, P. hirsuta, P. hydropiper, P. hydropiperoides, P. lapathifolia, P. longiseta, P. maculosa, P. meisneriana, P. minor, P. nepalensis, P. orientalis, P. pensylvanica, P. perfoliata, P. punctata, P. sagittata, P. setacea, P. virginiana, P. wallichii
Synonyms Polygonum longisetum, P. caespitosa var. longiseta, Polygonum caespitosum var. longisetum Polygonum punctatum var. robustius, P. punctata var. robustior, Polygonum punctatum var. majus, Polygonum robustius
Name authority (Bruijn) Kitagawa: Rep. Inst. Sci. Res. Manchoukuo 1: 322. (1937) (Small) E. P. Bicknell: Bull. Torrey Bot. Club 36: 455. (1909)
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