Persicaria punctata |
Polygonaceae subfam. polygonoideae |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
dotted knotweed, dotted smartweed, renouée ponctuée, water smartweed |
knotweed |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Habit | Plants annual or perennial, 1.5–12 dm; roots also often arising from proximal nodes; rhizomes often present. | Trees, shrubs, vines, or herbs, perennial or annual, homophyllous (heretophyllous in some species of Polygonum); root fibrous or a solid taproot, rarely tuberous. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Stems | ascending to erect, branched, without noticeable ribs, glabrous, glandular-punctate. |
usually prostrate to erect, sometimes scandent, not scapose, rarely with recurved spines (some species of Persicaria), glabrous or pubescent, sometimes glandular; nodes usually swollen; branches free (adnate to stems distal to nodes and appearing to arise internodally in Polygonella); tendrils absent (except in Antigonon and Brunnichia). |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Leaves | ocrea brown, cylindric, (4–)9–18 mm, chartaceous, base inflated, margins truncate, ciliate with bristles 2–11 mm, surface glabrous or strigose, glandular-punctate; petiole 0.1–1 cm, glandular-punctate, leaves sometimes sessile; blade without dark triangular or lunate blotch adaxially, lanceolate to lanceolate-ovate or subrhombic, 4–10(–15) × 0.6–2.4 cm, base tapered or cuneate, margins antrorsely strigose, apex acute to acuminate, faces glabrous or scabrous along midveins, glandular-punctate. |
deciduous (persistent in Coccoloba and sometimes more than 1 year in Antigonon and Polygonella), basal or basal and cauline, rarely cauline only, mostly alternate; ocrea present, persistent or deciduous, cylindric to funnelform, chartaceous, membranous, coriaceous, or, rarely, foliaceous or partly so; petiole present or absent, rarely articulate basally (Fagopyrum, Fallopia, Polygonella, Polygonum), rarely with extrafloral nectaries (Fallopia, Muehlenbeckia); blade simple with entire margins, rarely undulate or lobed. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Inflorescences | mostly terminal, sometimes also axillary, erect, interrupted, 50–200 × 4–8 mm; peduncle 30–60 mm, glabrous, glandular-punctate; ocreolae mostly not overlapping, margins mostly ciliate with bristles to 2 mm. |
terminal or terminal and axillary, spikelike, racemelike, paniclelike, cymelike, or, rarely, capitate, comprising simple or branched clusters of compound inflorescences; bracts absent; peduncle spreading to erect, sometimes absent; clusters of flowers subtended by connate bracteoles forming persistent membranous tube (ocreola), awnless. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pedicels | ascending, 1–4 mm. |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Flowers | 2–6 per ocreate fascicle, homostylous; perianth greenish proximally, white distally, rarely tinged pink, glandular-punctate with punctae ± uniformly distributed, scarcely accrescent; tepals 5, connate ca. 1/3 their length, obovate, 3–3.5 mm, veins prominent or not, not anchor-shaped, margins entire, apex obtuse to rounded; stamens 6–8, included; anthers pink or red, elliptic to ovate; styles 2–3, connate proximally. |
usually bisexual, sometimes bisexual and unisexual on same plant, rarely unisexual only, 1–20+ per ocreate fascicle, often with stipelike base distal to articulation; perianth often accrescent in fruit, often greenish, white, pink, yellow, red, or purple, usually unwinged and unkeeled (winged or, sometimes, keeled in Fallopia, rarely keeled in Polygonum), campanulate or urceolate, sometimes membranous, indurate, or fleshy in fruit, rarely developing raised tubercles proximally (Rumex), glabrous or pubescent, sometimes glandular or glandular-punctate; tepals 2–6, usually in 2 whorls, distinct or connate proximally and forming tube, petaloid or sepaloid, monomorphic or dimorphic; nectary a disk at base of ovary or glands associated with bases of filaments; stamens usually (1–)6–9, staminodes rarely present; filaments distinct, or connate basally and sometimes forming staminal tube, free or adnate to perianth tube; pistils (2–)3(–4)-carpellate; ovary 1-locular (sometimes with vestigial partitions proximally); ovule 1, orthotropous or, rarely, anatropous, placentation basal or free-central; styles 1–3, erect to spreading or recurved, distinct or connate proximally; stigmas peltate, capitate, fimbriate, or penicillate. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Achenes | included or apex exserted, brownish black, usually 3-gonous, rarely biconvex, (1.8–)2.2–3.2 × 1.5–2.2 mm, shiny, smooth. |
yellowish, brown, red, or black, homocarpic (sometimes heterocarpic in Polygonum), winged or unwinged, usually 2–3-gonous, sometimes discoid, biconvex, or spheroidal, rarely 4-gonous. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Seeds | embryo usually straight or curved, rarely folded. |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
2n | = 44. |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Persicaria punctata |
Polygonaceae subfam. polygonoideae |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Phenology | Flowering Jun–Nov. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Habitat | Shallow water, shores, marshes, floodplain forests | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Elevation | 0-1500 m (0-4900 ft) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Distribution |
AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; VA; VT; WA; WI; WV; WY; HI; BC; MB; NB; NS; ON; PE; QC; SK; Mexico; West Indies (Puerto Rico); Central America (Guatemala); South America (Brazil)
|
Mainly temperate regions of North America |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Discussion | N. C. Fassett (1949) proposed a complicated classification for Persicaria punctata with 12 varieties in North America and South America. He also identified numerous specimens that he considered to be morphologically intermediate between various varieties. M. Dalci (1972) documented a wide range of phenotypic and genotypic variation throughout the range of P. punctata and extensive overlap in many of the features used by Fassett to distinguish varieties. Consequently, recognition of varieties does not seem warranted. Persicaria punctata and its close relatives P. robustior and P. glabra are unique among native North American smartweeds in possessing complex glands called valvate chambers in their epidermises. Persicaria punctata is confused most frequently with P. hydropiper; the achenes are diagnostic. The Chippewa, Houma, and Iroquois prepared decoctions from leaves, flowers, and roots for use as analgesics as well as gastrointestinal, orthopedic, and psychological aids (D. E. Moerman 1998). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Genera 28, species ca. 850 (16 genera, 160 species in the flora). Morphological (K. Haraldson 1978; L.-P. Ronse Decraene and J. R. Akeroyd 1988; Ronse Decraene et al. 2000; Hong S. P. et al. 1998) and molecular (A. S. Lamb Frye and K. A. Kron 2003) data provide support for separation of Persicaria from Polygonum. Further studies are needed to elucidate the relationships of allied genera, particularly Aconogonon, Bistorta, and Koenigia with Persicaria, and Fallopia and Polygonella with Polygonum. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Key |
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Source | FNA vol. 5, p. 586. | FNA vol. 5, p. 479. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Parent taxa | Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Persicaria | Polygonaceae | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Sibling taxa | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Subordinate taxa | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Synonyms | Polygonum punctatum, Polygonum acre var. leptostachyum, Polygonum punctatum var. confertiflorum, Polygonum punctatum var. ellipticum, Polygonum punctatum var. leptostachyum, Polygonum punctatum var. parviflorum, Polygonum punctatum var. parvum | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Name authority | (Elliott) Small: Fl. S.E. U.S., 379. (1903) | Eaton: Bot. Dict. ed. 4, 30. (1836) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Web links |
|