Persicaria minor |
Persicaria bungeana |
|
---|---|---|
Asian knotweed, petite renouée, pygmy smartweed, small smartweed, small water-pepper |
prickly 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 not also arising from proximal nodes. |
Stems | decumbent or ascending, branched proximally, scarcely ribbed, glabrous or scabrous distally. |
ascending to erect, ribbed or obscurely so, glabrous or glandular-pubescent distally; prickles 1–1.5 mm. |
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 brownish, cylindric, 8–14 mm, chartaceous, base inflated or not, without prickles, margins truncate, ciliate with bristles 2–4 mm, surface with appressed bristles along veins; petiole 0.5–1.5 cm; blade lanceolate to narrowly elliptic, 5–12.5 × 1.5–3.5 cm, base acute, margins entire, antrorsely ciliate, apex acute acuminate, rarely obtuse, faces glabrous or pubescent and, usually, with antrorse prickles along midvein abaxially and adaxially. |
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. |
racemelike, uninterrupted or interrupted proximally, 20–45 × 5–10 mm; peduncle 20–40 mm, usually stipitate-glandular at least proximally; ocreolae usually overlapping, sometimes not overlapping proximally, margins eciliate. |
Pedicels | ascending, 0.5–1 mm. |
mostly ascending, 2–3 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. |
2–4 per ocreate fascicle; perianth pale green, often tinged red, glabrous, accrescent, not becoming blue and fleshy in fruit; tepals 5, connate 1/4–1/3 their length, petaloid, elliptic to broadly elliptic, 3–4 mm, apex obtuse; stamens 8, filaments distinct, free; anthers pink, ovate; styles 2, connate to middle. |
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, black, biconvex, 2.5–3 × 2.3–2.8 mm, dull, rugose. |
Persicaria minor |
Persicaria bungeana |
|
Phenology | Flowering Jul–Oct. | Flowering Jul–Sep. |
Habitat | Damp, open places | Cultivated fields |
Elevation | 0-100 m (0-300 ft) | 300-400 m (1000-1300 ft) |
Distribution |
CT; IN; LA; MA; NE; PA; VA; VT; NB; ON; QC; Europe [Introduced in North America]
|
IA; IL; MN; e Asia (n China, Japan, Korea, Manchuria) [Introduced in North America] |
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 bungeana is a weed of soybean fields (R. N. Andersen et al. 1985). It is not known how or when it was introduced into the midwestern United States. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 593. | FNA vol. 5, p. 578. |
Parent taxa | Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Persicaria | Polygonaceae > subfam. Polygonoideae > Persicaria > sect. Echinocaulon |
Sibling taxa | ||
Synonyms | Polygonum minus, Polygonum minus var. subcontinuum | Polygonum bungeanum |
Name authority | (Hudson) Opiz: Seznam, 72. (1852) | (Turczaninow) Nakai: in T. Mori, Enum. Pl. Corea, 131. (1922) |
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