Rumex obtusifolius |
Rumex hesperius |
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bitter dock, broad-leaf dock, broad-leaf or broadleaf or bitter dock, patience a feuilles obtuses |
western willow dock |
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Habit | Plants perennial, glabrous or ± papillose especially on veins of leaf blades abaxially, with fusiform, vertical rootstock. | Plants perennial, glabrous, with vertical rootstock. |
Stems | erect, branched distal to middle or occasionally in distal 2/3, often with few flowering stems from rootstock, 60–120(–150) cm. |
usually ascending, usually producing axillary shoots below 1st-order inflorescence or at proximal nodes, 30–50(–60) cm. |
Leaves | ocrea deciduous to partially persistent at maturity; blade oblong to ovate-oblong, sometimes broadly ovate, 20–40 × 10–15 cm, usually less than 4 times as long as wide, base normally distinctly cordate, occasionally rounded, rarely truncate, margins normally entire, flat or undulate, rarely slightly crisped, apex obtuse or subacute. |
blades light or yellowish green, veins scarcely prominent abaxially, elliptic-lanceolate, occasionally lanceolate, 6–12 × (2–)3–6 cm, usually (2–)3(–5) times as long as wide, widest near middle, thin, not coriaceous, base cuneate, margins entire, undulate, apex acute, warty in appearance. |
Inflorescences | terminal, occupying distal 2/3 of stem, usually lax and interrupted, narrowly or broadly paniculate, branches usually forming angle of 30–45° with 1st-order stem. |
terminal and axillary, terminal usually occupying distal 1/5–1/3 of stem, dense or interrupted near base, usually broadly paniculate (branches simple or with few 2d-order branches). |
Pedicels | articulated in proximal 1/3 or rarely near middle, filiform, 2.5–8.5(–10) mm, articulation distinctly swollen. |
articulated in proximal 1/3, filiform (but thickened distally), 3–6 mm, not more than 2–2.5 times as long as inner tepals, articulation indistinctly swollen. |
Flowers | 10–25 in lax whorls; inner tepals ovate-triangular, deltoid or, occasionally, lingulate, 3–6 × 2–3.5 mm (excluding teeth), ca. 1.5–2 times as long as wide, base truncate, margins usually distinctly dentate, rarely subentire, apex obtuse to subacute, straight, teeth 2–5, normally at each side of margin, short-subulate or triangular-subulate, straight, 0.5–1.8 mm, or shorter than width of inner tepals; tubercle usually 1, sometimes 3, then 1 distinctly larger, smooth. |
10–20 in whorls; inner tepals, triangular, broadly triangular, or deltoid, 3–4 × 3.5–4(–5) mm, base truncate, margins entire, apex acute or subacute; tubercle 1, small, narrow, much narrower than inner tepals, smooth to weakly rugose. |
Achenes | brown to reddish brown, 2–2.7 × 1.2–1.7 mm. |
not seen. |
2n | = 40. |
= 20. |
Rumex obtusifolius |
Rumex hesperius |
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Phenology | Flowering late spring–early fall. | Flowering late spring–early summer. |
Habitat | Waste places, roadsides, fields, shores, meadows, wet woods, swamps | Wet, alluvial habitats: shores, ditches |
Elevation | 0-2300 m (0-7500 ft) | 500-1000 m (1600-3300 ft) |
Distribution |
AK; 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; NE; NH; NJ; NM; NY; OH; OK; OR; PA; RI; SC; TN; TX; UT; VA; VT; WA; WI; WV; BC; NB; NF; NS; ON; PE; QC; SPM; Greenland; Europe; w Asia [Introduced in North America; introduced elsewhere]
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WA |
Discussion | Rumex obtusifolius, a member of subsect. Obtusifolii Rechinger f. (K. H. Rechinger 1937), is a polymorphic species represented in Eurasia by three or four rather distinct races often treated by European authors as subspecies or varieties. These taxa differ mostly in inner tepal dentation and geographic distribution. In North America the morphotypes often intergrade. In Eurasia this species is differentiated into predominantly western subsp. obtusifolius [including R. obtusifolius subsp. agrestis (Fries) Danser], eastern subsp. sylvestris (Wallroth) Rechinger f., intermediate central European subsp. transiens (Simonkai) Rechinger f., and montane subsp. subalpinus (Schur) Simonkai. Only subspp. obtusifolius and sylvestris occur in North America; the former seems to be more common. Subspecies obtusifolius differs from subsp. sylvestris in having larger and more prominently dentate inner tepals with one tubercle, or with three distinctly unequal tubercles; in subsp. sylvestris the teeth are usually less than 0.6 mm, developing only near the base of the inner tepals, and the tubercles often almost subequal. Rumex obtusifolius may be expected elsewhere in the Great Plains region of the United States and Canada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Rumex hesperius is a little-known species reported only from a localized area in Washington. According to N. M. Sarkar (1958) it is “quite distinct from other species” in its general appearance—a small plant with large, broad leaves and compact inflorescences. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 526. | FNA vol. 5, p. 513. |
Parent taxa | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Rumex | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Axillares |
Sibling taxa | ||
Synonyms | R. crispatulus, R. rugelii | |
Name authority | Linnaeus: Sp. Pl. 1: 335. (1753) | Greene: Pittonia 4: 234. (1901) |
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