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r enouée robuste, stout dotted smartweed, stout smartweed

knotweed, smartweed, tearthumb

Habit Plants perennial, 3–20 dm; roots also sometimes arising from proximal nodes; rhizomes present, stolons sometimes present. Herbs, perennial or annual (sometimes suffrutescent in P. wallichii); taprooted or fibrous-rooted; sometimes rhizomatous or stoloniferous.
Stems

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

branches sometimes creeping and rooting at nodes.

erect or, sometimes, prostrate or scandent, simple or branched, glabrous or pubescent, rarely with recurved prickles.

Leaves

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.

deciduous, mostly cauline, alternate, petiolate or sessile;

ocrea persistent or disintegrating with age and deciduous entirely or distally, usually tan, brown, or reddish, chartaceous or partially to entirely foliaceous, rarely coriaceous proximally and chartaceous distally, glabrous or scabrous to variously pubescent, never 2-lobed distally;

blade lanceolate or ovate to hastate or sagittate, margins entire or, rarely, hastately lobed.

Inflorescences

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.

terminal or terminal and axillary, spikelike, paniclelike, or capitate;

peduncle present.

Pedicels

ascending to spreading, 2–5 mm.

present or absent.

Flowers

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.

bisexual (often functionally unisexual in P. amphibia and P. hydropiperoides), 1–14 per ocreate fascicle, base not stipelike;

perianth white, greenish white, roseate, red, or purple, campanulate or urceolate, rarely rotate, rarely becoming fleshy in fruit, glabrous, sometimes glandular-punctate, accrescent or nonaccrescent;

tepals 4–5, connate 1/4–2/3 their lengths (less than 1/5 their lengths in P. wallichii), petaloid, dimorphic, outer larger than inner;

stamens 5–8, filaments distinct or connate basally, outer ones sometimes adnate to perianth tube, glabrous;

anthers yellow, pink, or red, elliptic to ovate;

styles 2–3, erect to spreading or reflexed, distinct or connate;

stigmas capitate.

Achenes

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

included or exserted, brown or dark brown to black, not winged, discoid, biconvex, 2–3-gonous, or spheroidal, glabrous.

Seeds

embryo curved.

x

= 10, 11, 12.

Persicaria robustior

Persicaria

Phenology Flowering Jul–Oct.
Habitat Peaty shores, often in water on coastal plain or near coast
Elevation 0-1500 m (0-4900 ft)
Distribution
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]
Nearly worldwide
[BONAP county map]
Discussion

Persicaria robustior often is synonymized with P. punctata.

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

Species ca. 100 (26 in the flora).

Opinions vary widely about the circumscription and infrageneric classification of Persicaria. The concept employed here generally follows L.-P. Ronse Decraene et al. (2000) and K. Haraldson (1978), with five sections recognized in the flora. Aconogonon and Bistorta, which often are included in Persicaria or in Polygonum in the broad sense, are treated here as separate genera.

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

Key

Key to the Sections of Persicaria

1. Styles exserted, persistent on achenes; inflorescences spikelike, interrupted
sect. Tovara
1. Styles included, rarely exserted, deciduous; inflorescences capitate, paniclelike, or spikelike, uninterrupted or interrupted
→ 2
2. Stems with recurved prickles, scandent or, rarely, ascending to erect
sect. Echinocaulon
2. Stems unarmed, usually erect or ascending, rarely prostrate or decumbent
→ 3
3. Inflorescences capitate; petioles usually winged, auriculate
sect. Cephalophilon
3. Inflorescence spikelike or paniclelike; petioles not winged, not auriculate
→ 4
4. Inflorescences paniclelike; perianths rotate; tepals connate less than 1/ 5 their lengths
sect. Rubrivena
4. Inflorescences spikelike; perianths campanulate; tepals connate 1/ 2/ 3 their lengths
sect. Persicaria
Source FNA vol. 5, p. 584. FNA vol. 5, p. 574. Authors: Harold R. Hinds†, Craig C. Freeman.
Parent taxa Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Persicaria Polygonaceae > subfam. Polygonoideae
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. 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
Subordinate taxa
P. sect. Cephalophilon, P. sect. Echinocaulon, P. sect. Persicaria, P. sect. Rubrivena, P. sect. Tovara
Synonyms Polygonum punctatum var. robustius, P. punctata var. robustior, Polygonum punctatum var. majus, Polygonum robustius Polygonum unranked P.
Name authority (Small) E. P. Bicknell: Bull. Torrey Bot. Club 36: 455. (1909) (Linnaeus) Miller: Gard. Dict. Abr. ed. 4, vol. 3. (1754)
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