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common sheep sorrel, field sorrel, oseille, petite oseille, red sorrel, sheep dock, sheep sorrel, sour weed, sûrette

grass-leaf sorrel

Habit Plants perennial, glabrous, with vertical rootstock and/or creeping rhizomes. Plants perennial, glabrous, with creeping rhizomes and elongated underground stolons.
Stems

erect or ascending, several from base, branched in distal 1/2 (in inflorescence), 10–40(–45) cm;

shoots variable.

erect or ascending, rarely almost prostrate, branched at base and in distal 1/2 (in inflorescence), 7–30(–40) cm;

shoots not crowded, ± elongated.

Leaves

ocrea brownish at base, silvery and lacerated in distal 1/2;

blade normally obovate-oblong, ovate-lanceolate, lanceolate-elliptic, or lanceolate, occasionally, linear-lanceolate to almost linear, 2–6 × 0.3–2 cm, base hastate (with spreading, entire or sometimes multifid, dissected lobes), occasionally without evident lobes, then base broadly cuneate, margins entire, flat or nearly so, apex acute or obtuse.

ocrea whitish or silvery, membranous;

blade normally narrowly linear, or occasionally linear-lanceolate, usually not hastate, rarely some with indistinct basal lobes, 3–10 × 0.1–0.2(–0.4) cm, base narrowly cuneate, margins entire, flat or occasionally slightly revolute, apex acute or obtuse.

Inflorescences

terminal, usually occupying distal 1/2–2/3 of stem, usually lax and interrupted to top, broadly or narrowly paniculate.

terminal, occupying distal 2/3 of stem, usually lax and interrupted to top, paniculate, with branches often reflexed.

Pedicels

1–3 mm.

1–4 mm.

Flowers

(3–)5–8(–10) in whorls;

inner tepals not or slightly enlarged, normally 1.2–1.7(–2) × 0.5–1.3 mm (free wing absent or barely visible), base cuneate, apex obtuse or subacute.

(3–)4–6(–8) in whorls;

inner tepals distinctly enlarged, normally 2–2.6 × 1.5–2(–2.2) mm (free wing 0.3–0.5 mm wide), base cuneate, apex obtuse or subacute.

Achenes

brown or dark brown, 0.9–1.5 × 0.6–0.9 mm.

brown or yellowish brown, 1.5–2 × 1–1.5 mm.

2n

= 14, 28, 42.

= 56.

Rumex acetosella

Rumex graminifolius

Phenology Flowering spring–summer. Flowering late spring–summer.
Habitat Roadsides, cultivated fields, waste places, disturbed areas, lawns, meadows, railroad gravels, sandy and muddy shores: usually in acidic soils Sandy and gravelly shores and slopes
Elevation 0-2700 m (0-8900 ft) 0-400 m (0-1300 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; 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; ON; PE; QC; SK; YT; SPM; Greenland; Europe; w Asia [Introduced in North America; introduced almost worldwide]
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; Greenland; n Eurasia
Discussion

Rumex acetosella in the broad sense is an extremely variable and taxonomically complicated polyploid complex, which includes diploids, tetraploids, hexaploids, and octoploids. This complex (excluding more distantly related arctic-montane R. graminifolius and its allies) probably originated and developed mostly in southern Europe and southwestern Asia. Some races of R. acetosella now are distributed almost worldwide as introduced and often completely naturalized aliens.

Á. Löve (1941, 1983) assumed that in this group chromosome numbers are strictly correlated with morphology. In his opinion, every chromosome race represents a distinct species: diploid Rumex angiocarpus Murbeck [= Acetosella angiocarpa (Murbeck) Á. Löve]; tetraploid R. multifidus Linnaeus [= R. tenuifolius (Wallroth) Á. Löve = Acetosella multifida (Linnaeus) Á. Löve]; hexaploid R. acetosella in the narrow sense [= A. vulgaris (W. D. J. Koch) Fourreau, with gymnocarpous A. vulgaris subsp. vulgaris and angiocarpous A. vulgaris subsp. pyrenaica (Pourret ex Lapeyrouse) Á. Löve]; hexaploid R. graminifolius Rudolph ex Lambert [= A. graminifolia (Rudolph ex Lambert) Á. Löve]. However, the distribution given by Löve for these taxa seems unnatural. Studies by J. C. M. den Nijs and collaborators (den Nijs 1974, 1976, 1984; den Nijs and T. Panhorst 1980; den Nijs et al. 1980, 1985; see also W. Harris 1969, 1973) indicate that the situation is more complicated. They postulated the development of two major evolutionary lines into two ploidy complexes: a primary western Mediterranean one and a secondary eastern Mediterranean one. According to this scheme, polyploid races independently and spontaneously emerged (and still are emerging) within different ancestral populations.

The most widespread, almost cosmopolitan race, presumably native to the southwestern Mediterranean region, including southwestern and Atlantic Europe, which is common in North America, is characterized by a hexaploid chromosome set (2n = 42), nonmultifid lateral lobes of basal leaves, and angiocarpy (fruits are not easily separable from accrescent inner tepals). It was commonly and erroneously referred to as Rumex angiocarpus Murbeck, or R. acetosella subsp. angiocarpus (Murbeck) Murbeck. According to J. R. Akeroyd (1991), who in general followed the taxonomic revision of the group by J. C. M. den Nijs (1984), the correct name for this taxon is R. acetosella subsp. pyrenaicus (Pourret ex Lapeyrouse) Akeroyd (=Acetosella vulgaris subsp. pyrenaica (Pourret ex Lapeyrouse) Á. Löve). Gymnocarpous nonmultifid and multifid forms (R. acetosella subsp. acetosella and R. acetosella subsp. acetoselloides (Balansa) den Nijs, respectively) also occur in North America, but evidently rarely. The distributions of subspecies of R. acetosella in North America are poorly known. Keys and detailed descriptions for the subspecies were provided by den Nijs and Akeroyd. However, the tempting simplicity of the keys is somewhat suspicious. The alternative point of view (and an alternative key) may be found in Á. Löve (1983).

Rumex acetosella subsp. arenicola Mäkinen ex Elven was recently described from Greenland and reported for Scandinavia and arctic Russia (R. Elven et al. 2000). This entity seems to be morphologically transitional toward Rumex graminifolius (see discussion under that species below). According to Elven et al., it differs from other infraspecific entities of R. acetosella in having the following characters: leaves usually without basal lobes (as in R. graminifolius), with revolute margins; inflorescence sparsely branched; tepals and pedicels densely covered with red papillae (as in R. graminifolius). From R. graminifolius and related taxa (R. beringensis and R. krausei) it can be distinguished by narrower inner tepals (similar in size to those in other subspecies of R. acetosella). The distribution of subsp. arenicola and its relations to other taxa are in need of further study.

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

Records of Rumex graminifolius from Alaska in most cases refer to R. beringensis and R. krausei. The occurrence of typical R. graminifolius in northwestern North America remains uncertain. Some literature records of R. acetosella from northeastern North America (Greenland, Labrador, Newfoundland) may refer to R. graminifolius or R. acetosella subsp. arenicola. Rumex graminifolius was reported from Newfoundland also by M. L. Fernald (1950), but that record requires confirmation.

Some plants from northeastern Eurasia (northeastern Russian Far East and northern Siberia) are known in Russian literature as Rumex aureostigmaticus Komarov [Acetosella aureostigmatica (Komarov) Tzvelev], R. acetosella var. subspathulatus Trautvetter, or R. graminifolius var. subspathulatus (Trautvetter) Tolmatchew (see A. I. Tolmachew 1966; N. N. Tzvelev 1989b). They differ from R. graminifolius in having narrower inner tepals and wider spatulate leaves, usually without basal lobes. I have seen only one North American collection approaching this entity. Some specimens (mostly immature or staminate plants) from western Alaska differ from both R. graminifolius and R. beringensis in their habit; they need additional study. Some chromosome counts different from the most typical number (2n = 56) that have been reported for R. graminifolius in the broad sense from northeastern Russian Far East by several Russian authors (see references in Tzvelev) most probably also refer to R. aureostigmaticus. It is also possible that arctic and subarctic plants identified by various authors as R. aureostigmaticus, R. acetosella var. subspathulatus, R. graminifolius var. subspathulatus, and R. acetosella subsp. arenicola belong to one polymorphic complex of plants intermediate between R. acetosella and R. graminifolius.

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

Source FNA vol. 5, p. 498. FNA vol. 5, p. 499.
Parent taxa Polygonaceae > subfam. Polygonoideae > Rumex > subg. Acetosella Polygonaceae > subfam. Polygonoideae > Rumex > subg. Acetosella
Sibling taxa
R. acetosa, 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. 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. 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 Acetosa acetosella, Acetosa hastata, Acetosa vulgaris, R. acetosella var. vulgaris Acetosella graminifolia, R. acetosella var. graminifolius, R. angustissimus
Name authority Linnaeus: Sp. Pl. 1: 338. (1753) Rudolph ex Lambert: Trans. Linn. Soc. London 10: 264, plate 10. (1811)
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