Rumex mexicanus |
Rumex densiflorus |
|
---|---|---|
Mexican dock, Mexican willow, Mexican willow or dock |
dense-flower dock |
|
Habit | Plants perennial, glabrous; with vertical rootstock, occasionally with short, creeping rhizomes. | Plants perennial, glabrous or indistinctly papillose-pubescent, with creeping horizontal rhizome. |
Stems | erect or ascending, usually producing axillary shoots below 1st-order inflorescence or at proximal nodes, 30–60(–90) cm. |
erect, branched above middle (only in inflorescence), 50–100 cm. |
Leaves | 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. |
ocrea deciduous or partially persistent at maturity; blade with large lateral veins alternating with short ones, oblong or oblong-lanceolate, 30–40(–50) × 10–12 cm, more than 3 times as long as wide, base broadly cuneate, truncate, or weakly cordate, margins entire or indistinctly repand, flat, apex obtuse or broadly 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, occupying distal 1/2 of stem, usually dense, narrowly paniculate. |
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, 6–16 mm, articulation indistinct. |
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 in whorls; inner tepals ovate-triangular or subcordate, 5–6 × 4.5–6 mm, widest at or near middle, base weakly emarginate, margins entire, erose, or indistinctly denticulate mostly at base, apex abruptly narrowed, acute or subacute; tubercles absent. |
Achenes | brown or dark reddish brown, 2–3 × 1.5–2 mm. |
deep brown to reddish brown, 2.5–4(–4.5) × 1.8–2.5 mm. |
2n | = 40. |
= 120. |
Rumex mexicanus |
Rumex densiflorus |
|
Phenology | Flowering spring–early summer. | Flowering late spring–early summer. |
Habitat | Shores of streams and rivers, wet meadows | Along streams and rivers in montane, subalpine, and alpine zones |
Elevation | 1000 m (3300 ft) | 1500-3000(-3500) m (4900-9800(-11500) ft) |
Distribution |
NM; Mexico
|
CO; NM; WY
|
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.) |
The following three species are closely related to Rumex densiflorus, all belonging to subsect. Densiflori Rechinger f., and possibly form one polymorphic “macrospecies” (K. H. Rechinger 1937). Á. Löve (1986) treated R. orthoneurus and R. pycnanthus as subspecies of R. densiflorus. However, the variability of this aggregate is insufficiently known, and I prefer to treat it as consisting of four “microspecies.” Rumex densiflorus is reported from northwestern New Mexico (W. C. Martin and C. R. Hutchins 1980), where it most probably occurs; records for southern Idaho (R. J. Davis 1952) and Arizona (J. H. Lehr 1978) need confirmation. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 511. | FNA vol. 5, p. 515. |
Parent taxa | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Axillares | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Rumex |
Sibling taxa | ||
Synonyms | R. polyrrhizus | |
Name authority | Meisner: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 45. (1856) | Osterhout: Erythea 6: 13. (1898) |
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