Persicaria minor |
Persicaria longiseta |
|
---|---|---|
Asian knotweed, petite renouée, pygmy smartweed, small smartweed, small water-pepper |
bristly lady's-thumb, oriental lady's thumb, oriental lady's-thumb smartweed |
|
Habit | Plants annual, 0.5–3(–4) dm; roots also sometimes at from proximal nodes; rhizomes and stolons absent. | Plants annual, 3–8 dm; roots also often arising from proximal nodes; rhizomes and stolons absent. |
Stems | decumbent or ascending, branched proximally, scarcely ribbed, glabrous or scabrous distally. |
decumbent to ascending, branched, without noticeable ribs, glabrous. |
Leaves | ocrea brownish, cylindric, 3–10 mm, chartaceous, base not inflated, margins truncate, ciliate with bristles (0.3–)1–3(–5) mm, surface glabrous or strigose, not glandular-punctate; petiole 0.1–0.2 cm, glabrous or strigose, leaves sometimes sessile; blade without dark triangular or lunate blotch adaxially, linear to linear-lanceolate, (1–)2–7.5(–10) × (0.2–)0.4–1(–2.3) cm, base tapered to cuneate, margins antrorsely scabrous, apex acute to acuminate, faces glabrous or sparingly strigose, especially along midveins, not glandular-punctate. |
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. |
Inflorescences | terminal and axillary, ascending to erect, usually interrupted proximally, uninterrupted distally, 10–50 × 2–4 mm; peduncle (0–)2–25 mm, sometimes absent on axillary inflorescences and flowers thus enclosed in ocreae, glabrous; ocreolae not overlapping proximally, usually overlapping distally, margins ciliate with bristles (0.1–)0.6–2(–2.7) mm. |
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. |
Pedicels | ascending, 0.5–1 mm. |
ascending, 1–2 mm. |
Flowers | 1–3(–4) per ocreate fascicle, homostylous; perianth roseate to red, rarely white, glabrous, not glandular-punctate, scarcely accrescent; tepals 5, connate ca. 1/3 their length, obovate to elliptic, 2.5–3 mm, veins not prominent, not anchor-shaped, margins entire, apex obtuse to rounded; stamens 5(–6), included; anthers yellow to pink, elliptic; styles 2(–3), connate at bases. |
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. |
Achenes | included, brownish black to black, biconvex or, rarely, 3-gonous, (1.5–)1.8–2.3(– 2.7) × (1.1–)1.3–1.5(–1.8) mm, shiny, smooth. |
included, dark brown to black, 3-gonous, 1.6–2.3 × 1.1–1.6 mm, shiny, smooth. |
Persicaria minor |
Persicaria longiseta |
|
Phenology | Flowering Jul–Oct. | Flowering May–Oct. |
Habitat | Damp, open places | Floodplain forests and woodlands, shorelines of ponds, moist roadsides, waste places |
Elevation | 0-100 m (0-300 ft) | 0-300 m (0-1000 ft) |
Distribution |
CT; IN; LA; MA; NE; PA; VA; VT; NB; ON; QC; Europe [Introduced in North America]
|
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]
|
Discussion | Persicaria minor is synonymized with P. maculosa in most North American floras; its distribution in the flora area is poorly known. Hybrids between P. minor and P. maculosa have been documented in Europe (R. H. Roberts 1977). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 5, p. 593. | FNA vol. 5, p. 592. |
Parent taxa | Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Persicaria | Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Persicaria |
Sibling taxa | ||
Synonyms | Polygonum minus, Polygonum minus var. subcontinuum | Polygonum longisetum, P. caespitosa var. longiseta, Polygonum caespitosum var. longisetum |
Name authority | (Hudson) Opiz: Seznam, 72. (1852) | (Bruijn) Kitagawa: Rep. Inst. Sci. Res. Manchoukuo 1: 322. (1937) |
Web links |
|