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Mexican dock, Mexican willow, Mexican willow or dock

curled dock, curly dock, patience crépue, reguette, rumex crépu, sour dock, yellow dock

Habit Plants perennial, glabrous; with vertical rootstock, occasionally with short, creeping rhizomes. Plants perennial, occasionally biennial, glabrous or very indistinctly papillose normally only on veins of leaf blades abaxially, with fusiform, vertical rootstock.
Stems

erect or ascending, usually producing axillary shoots below 1st-order inflorescence or at proximal nodes, 30–60(–90) cm.

erect, branched distal to middle, 40–100(–150) 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, rarely partially persistent at maturity;

blade lanceolate to narrowly lanceolate or lanceolate-linear, normally 15–30(–35) × 2–6 cm, base cuneate, truncate, or weakly cordate, margins entire to subentire, strongly crisped and 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, occupying distal 1/2 of stem, dense or interrupted at base, narrowly to broadly paniculate, branches usually straight or arcuate.

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, (3–)4–8 mm, articulation distinctly 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).

10–25 in whorls;

inner tepals orbiculate-ovate or ovate-deltoid, 3.5–6 × 3–5 mm, base truncate or subcordate, margins entire or subentire to very weakly erose, flat, apex obtuse or subacute;

tubercles normally 3, rarely 1 or 2, unequal, at least 1 distinctly larger, more than (1–)1.5 mm wide.

Achenes

brown or dark reddish brown, 2–3 × 1.5–2 mm.

usually reddish brown, 2–3 × 1.5–2 mm.

2n

= 40.

= 60.

Rumex mexicanus

Rumex crispus

Phenology Flowering spring–early summer. Flowering late spring–early fall.
Habitat Shores of streams and rivers, wet meadows Very broad range of ruderal, segetal, and seminatural habitats, disturbed soil, waste places, cultivated fields, roadsides, meadows, shores of water bodies, edges of woods
Elevation 1000 m (3300 ft) 0-2500 m (0-8200 ft)
Distribution
from FNA
NM; Mexico
[WildflowerSearch map]
[BONAP county map]
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; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK; YT; SPM; Eurasia [Introduced in North America; introduced almost worldwide]
[WildflowerSearch map]
[BONAP county map]
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 crispus (belonging to subsect. Crispi Rechinger f.; see K. H. Rechinger 1937) is the most widespread and ecologically successful species of the genus, occuring almost worldwide as a completely naturalized and sometimes invasive alien. It has not been reported from Greenland, but it probably occurs there.

Rumex crispus hybridizes with many other species of subg. Rumex. Hybrids with R. obtusifolius (Rumex ×pratensis Mertens & Koch) are the most common in the genus, at least in Europe, and have been reported for several localities in North America. Rumex crispus × R. patientia (Rumex ×confusus Simonkai) was reported from New York. According to R. S. Mitchell (1986, p. 47), “this hybrid is now spreading along highway shoulders, and it has replaced R. crispus in some local areas.” However, that information should be confirmed by more detailed studies since spontaneous hybrids between species of sect. Rumex usually are much less fertile and ecologically successful than the parental species. Hybrids of Rumex occuring in North America need careful revision.

Numerous infraspecific taxa and even segregate species have been described in the Rumex crispus aggregate. Many seem to represent minor variation of little or no taxonomic significance, but some are geographically delimited entities that may deserve recognition as subspecies or varieties. The typical variety has inner tepals with three well-developed tubercles; the less common var. unicallosus Petermann, with one tubercle, occurs sporadically in North America.

Some eastern Asian plants differ from typical Rumex crispus is having somewhat smaller inner tepals, longer pedicels, lax inflorescences with remote whorls, and narrower leaves that are almost flat or indistinctly undulate at the margins. These plants, originally described as R. fauriei Rechinger f., are now treated as R. crispus subsp. fauriei (Rechinger f.) Mosyakin & W. L. Wagner; the subspecies was recently reported from Hawaii (S. L. Mosyakin and W. L. Wagner 1998) and may be expected as introduced in western North America.

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

Source FNA vol. 5, p. 511. FNA vol. 5, p. 522.
Parent taxa Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Axillares 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. nematopodus, R. obovatus, R. obtusifolius, 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. 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. 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
Synonyms Lapathum crispum
Name authority Meisner: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 45. (1856) Linnaeus: Sp. Pl. 1: 335. (1753)
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