Rumex mexicanus |
Rumex sibiricus |
|
---|---|---|
Mexican dock, Mexican willow, Mexican willow or dock |
Siberian dock, Siberian or Siberian willow dock |
|
Habit | Plants perennial, glabrous; with vertical rootstock, occasionally with short, creeping rhizomes. | Plants perennial, glabrous, with vertical rootstock. |
Stems | erect or ascending, usually producing axillary shoots below 1st-order inflorescence or at proximal nodes, 30–60(–90) cm. |
usually ascending, occasionally erect, usually producing axillary shoots below 1st-order inflorescence, especially at proximal nodes, 15–40(–70) cm. |
Leaf | blades light green to yellowish green, linear-lanceolate, occasionally lanceolate, 6–14 × 1–3.5(–4) cm, usually ca. 5–7 times as long as wide, widest near middle, thin, not coriaceous, base cuneate, margins entire, flat or undulate, apex acute or attenuate. |
blades linear-lanceolate or narrowly linear-lanceolate, 6–15 × 1–2(–2.5) mm, usually ca. 6–10 times as long as wide, widest near middle, thin, not coriaceous, base cuneate, margins entire, flat or undulate, apex acute. |
Inflorescences | terminal and axillary, terminal usually occupying distal 1/5–1/3 of stem, rather dense or interrupted in proximal 1/2, usually broadly paniculate (branches simple or with few 2d-order branches). |
terminal and axillary, terminal usually occupying distal 1/5–1/3 of stem, rather dense or occasionally interrupted in proximal 1/2, usually broadly paniculate (branches simple or with few 2d-order branches). |
Pedicels | articulated in proximal 1/3 or almost near base, filiform (thickened distally), 4–7 mm, not more than 2–2.5 times as long as inner tepals, articulation indistinctly swollen. |
articulated in proximal 1/3, filiform (but thickened distally), 1.5–3.5(–4) mm, not more than 2–2.5 times as long as inner tepals, articulation indistinctly swollen. |
Flowers | 10–20 in whorls; inner tepals broadly ovate-triangular, occasionally broadly triangular, 3.5–4.5(–5) × 3.5–4(–5) mm, base truncate or indistinctly cordate, margins entire or indistinctly erose, apex obtuse or subacute; tubercles 3, equal or subequal (much narrower than inner tepals). |
10–20(–25) in whorls; inner tepals ovate or occasionally ovate-lanceolate, 2.5–3(–3.5) × 1.6–2.5 mm, base broadly cuneate or truncate, margins entire or indistinctly erose, apex obtuse or subacute; tubercles 3, equal or subequal, usually distinctly narrower and much shorter than inner tepals, smooth or weakly rugose. |
Achenes | brown or dark reddish brown, 2–3 × 1.5–2 mm. |
dark brown, occasionally dark reddish brown, 2–2.5 × 1–1.2 mm. |
2n | = 40. |
= 20. |
Rumex mexicanus |
Rumex sibiricus |
|
Phenology | Flowering spring–early summer. | Flowering late spring–summer. |
Habitat | Shores of streams and rivers, wet meadows | Sandy, gravelly, and clayey shores of rivers and streams, wet rocky and grassy slopes |
Elevation | 1000 m (3300 ft) | 0-1500 m (0-4900 ft) |
Distribution |
NM; Mexico
|
AK; NT; YT; Asia (n Russian Far East including Kamchatka, Siberia) |
Discussion | Some authors recognize Rumex mexicanus in the broad sense, including in it many other taxa treated here as separate entities. For consistency, the entities of the R. salicifolius aggregate that are recognized herein are kept separate pending additional taxonomic research. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Rumex hultenii Tzvelev, a species closely related to R. sibiricus (it differs from the latter mostly by inner tepals without tubercles), was reported from Alaska by N. N. Tzvelev (1987b, 1989b). Rumex hultenii is reported to differ from R. utahensis by its narrower leaves, and from R. subarcticus by its smaller inner tepals and erect or ascending (not prostrate) habit, as well as by smaller inner tepals. Records of R. utahensis from Alaska may refer to R. hultenii. I have seen no reliable specimens from North America of R. hultenii and cannot confirm that it occurs in Alaska. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 511. | FNA vol. 5, p. 513. |
Parent taxa | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Axillares | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Axillares |
Sibling taxa | ||
Synonyms | R. salicifolius var. angustifolius | |
Name authority | Meisner: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 45. (1856) | Hultén: Kongl. Svenska Vetensk. Acad. Handl., ser. 3, 5(2): 48. (1928) |
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