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bitter dock, broad-leaf dock, broad-leaf or broadleaf or bitter dock, patience a feuilles obtuses

rumex occidental, western dock, western dock o n

Habit Plants perennial, glabrous or ± papillose especially on veins of leaf blades abaxially, with fusiform, vertical rootstock. Plants perennial, glabrous or very indistinctly papillose, especially on veins of leaf blades abaxially, with fusiform, vertical or oblique 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 erect, branched from above middle or in distal 2/3, 50–100(–140) 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.

ocrea deciduous or partially persistent at maturity;

blade narrowly ovate-triangular, ovate-lanceolate, or oblong-lanceolate, normally 10–35 × 5–12 cm, base weakly to distinctly cordate, truncate, or rounded, margins entire, undulate or indistinctly crisped, apex acute or subacute, rarely obtuse.

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, occupying distal 2/3 of stem, dense to interrupted, narrowly paniculate, often repeatedly branched (branches usually more than 7–8 cm).

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, 5–13(–17) mm, normally not more than 2–2.5 times as long as inner tepals, articulation weakly evident, not 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.

mostly 12–25 in whorls;

inner tepals orbiculate, ovate, or broadly ovate-triangular, 5–10(–12) × 5–8(–11) mm, base truncate to weakly cordate, margins entire or subentire to very weakly erose, apex obtuse or subacute;

tubercles absent.

Achenes

brown to reddish brown, 2–2.7 × 1.2–1.7 mm.

reddish brown, 3–4.5(–4.8) × 1.5–2.5 mm.

2n

= 40.

= 120.

Rumex obtusifolius

Rumex occidentalis

Phenology Flowering late spring–early fall. Flowering late spring–summer.
Habitat Waste places, roadsides, fields, shores, meadows, wet woods, swamps Wet meadows, bogs, marshes, river banks, shallow water, other wet habitats
Elevation 0-2300 m (0-7500 ft) 0-2500(-3000) m (0-8200(-9800) ft)
Distribution
from FNA
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]
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; AZ; CA; CO; IA; ID; ME; MN; MT; ND; NM; NV; OR; SD; UT; VT; WA; WY; AB; BC; MB; NF; NS; NT; ON; QC; SK; YT
[WildflowerSearch map]
[BONAP county map]
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.)

In the nineteenth century, Rumex occidentalis commonly was misidentified as R. aquaticus, R. longifolius, or R. domesticus.

All of the species of subsect. Aquatici Rechinger f., represented in North America by Rumex occidentalis, R. arcticus, R. nematopodus, and R. tomentellus, form a taxonomically complex aggregate with poorly delimited, often intergrading species. Extremes are evidently distinct (e.g., R. arcticus and R. tomentellus). The taxonomy and distribution of members of this aggregate are still insufficiently known. Some authors prefer to treat all or most of these taxa as subspecies or varieties of R. aquaticus in the broad sense. From my point of view, this does not promote a better understanding of their variability and relationships.

A number of segregate species have been described and recognized in regional floras in North America. In most cases the features upon which these species are based intergrade. One of the most widely recognized segregates is Rumex fenestratus Greene emend. Rechinger f. [R. aquaticus subsp. fenestratus (Greene) Hultén, R. occidentalis S. Watson subsp. fenestratus (Greene) Hultén], which, according to K. H. Rechinger (1937), may be distinguished mostly by larger and more cordate fruiting inner tepals (more than 7 mm in R. fenestratus, usually less than 7 mm in R. occidentalis), and larger achenes (3 mm, and more than 3.5 mm, respectively). The morphotype of R. fenestratus occurs mostly along the Pacific coast from central western California to Alaska. Plants with large fruiting inner tepals [known as R. fenestratus var. labradoricus Rechinger f. or R. occidentalis var. labradoricus (Rechinger f.) Lepage] occur also in eastern Canada (Newfoundland and Quebec). In this treatment, I follow the taxonomic decision by J. E. Dawson (1979), who carefully analyzed the clinal variability of the R. occidentalis aggregate. However, R. fenestratus probably deserves recognition at least as a subspecies of R. occidentalis, but its taxonomic status needs additional investigation.

Rumex occidentalis was reported also from New Brunswick (which seems to be a rather natural extension of its range); however, the present status of the species in that province is uncertain.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 5, p. 526. FNA vol. 5, p. 518.
Parent taxa Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Rumex Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Rumex
Sibling taxa
R. acetosa, R. acetosella, R. alpinus, R. altissimus, R. arcticus, R. beringensis, R. britannica, R. brownii, R. bucephalophorus, R. californicus, R. chrysocarpus, R. confertus, R. conglomeratus, R. crassus, R. crispus, R. cristatus, R. cuneifolius, R. densiflorus, R. dentatus, R. ellipticus, R. fascicularis, R. floridanus, R. fueginus, R. graminifolius, R. hastatulus, R. hesperius, R. hymenosepalus, R. kerneri, R. krausei, R. lacustris, R. lapponicus, R. longifolius, R. maritimus, R. mexicanus, R. nematopodus, R. obovatus, R. occidentalis, R. orthoneurus, R. pallidus, R. palustris, R. paraguayensis, R. patientia, R. paucifolius, R. persicarioides, R. praecox, R. pseudonatronatus, R. pulcher, R. pycnanthus, R. salicifolius, R. sanguineus, R. sibiricus, R. spiralis, R. stenophyllus, R. subarcticus, R. thyrsiflorus, R. tomentellus, R. transitorius, R. triangulivalvis, R. utahensis, R. venosus, R. verticillatus, R. violascens
R. acetosa, R. acetosella, R. alpinus, R. altissimus, R. arcticus, R. beringensis, R. britannica, R. brownii, R. bucephalophorus, R. californicus, R. chrysocarpus, R. confertus, R. conglomeratus, R. crassus, R. crispus, R. cristatus, R. cuneifolius, R. densiflorus, R. dentatus, R. ellipticus, R. fascicularis, R. floridanus, R. fueginus, R. graminifolius, R. hastatulus, R. hesperius, R. hymenosepalus, R. kerneri, R. krausei, R. lacustris, R. lapponicus, R. longifolius, R. maritimus, R. mexicanus, R. nematopodus, R. obovatus, R. obtusifolius, R. orthoneurus, R. pallidus, R. palustris, R. paraguayensis, R. patientia, R. paucifolius, R. persicarioides, R. praecox, R. pseudonatronatus, R. pulcher, R. pycnanthus, R. salicifolius, R. sanguineus, R. sibiricus, R. spiralis, R. stenophyllus, R. subarcticus, R. thyrsiflorus, R. tomentellus, R. transitorius, R. triangulivalvis, R. utahensis, R. venosus, R. verticillatus, R. violascens
Synonyms R. crispatulus, R. rugelii R. aquaticus subsp. fenestratus, R. aquaticus subsp. occidentalis, R. bakeri, R. fenestratus, R. fenestratus var. labradoricus, R. gracilipes, R. occidentalis subsp. fenestratus, R. occidentalis var. labradoricus
Name authority Linnaeus: Sp. Pl. 1: 335. (1753) S. Watson: Proc. Amer. Acad. Arts 12: 253. (1877)
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