''Oxalis acetosella'', the wood sorrel or common wood sorrel, is a

rhizomatous In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow ho ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the family '' Oxalidaceae'', common in most of

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

and parts of

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

. The specific epithet ''acetosella'' refers to its sour taste. The common name wood sorrel is often used for other plants in the genus ''Oxalis''. In much of its range it is the only member of its

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

and hence simply known as "the" wood sorrel. While common wood sorrel may be used to differentiate it from most other species of ''Oxalis'', in North America, ''

Oxalis montana ''Oxalis montana'' is a species of flowering plant in the family Oxalidaceae known by the common names mountain woodsorrel, wood shamrock, sours and white woodsorrel. It may also be called common woodsorrel, though this name also applies to its ...

'' is also called common wood sorrel. It is also known as ''Alleluia'' because it blossoms between

Easter Easter,Traditional names for the feast in English are "Easter Day", as in the '' Book of Common Prayer''; "Easter Sunday", used by James Ussher''The Whole Works of the Most Rev. James Ussher, Volume 4'') and Samuel Pepys''The Diary of Samuel ...

and Pentecost, when the

Psalms The Book of Psalms ( or ; he, תְּהִלִּים, , lit. "praises"), also known as the Psalms, or the Psalter, is the first book of the ("Writings"), the third section of the Tanakh, and a book of the Old Testament. The title is derived ...

which end with

Hallelujah ''Hallelujah'' ( ; he, ''haləlū-Yāh'', meaning "praise Yah") is an interjection used as an expression of gratitude to God. The term is used 24 times in the Hebrew Bible (in the book of Psalms), twice in deuterocanonical books, and four tim ...

are sung.

Description

The plant has trifoliate compound leaves, the leaflets heart-shaped and folded through the middle, that occur in groups of three on petioles up to long. It flowers from spring to midsummer with small white chasmogamous

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s with pink streaks. Red or violet flowers also occur rarely.Clapham, A.R., Tutin, T.G. and Warburg E.F. 1968. ''Excursion Flora of the British Isles''. Cambridge University Press. During the night or when it rains the flowers close and the leaves fold. As with other species of wood sorrel, the leaves are sometimes eaten. An

oxalate Oxalate (IUPAC: ethanedioate) is an anion with the formula C2O42−. This dianion is colorless. It occurs naturally, including in some foods. It forms a variety of salts, for example sodium oxalate (Na2C2O4), and several esters such as dimethyl ...

called "sal acetosella" was formerly extracted from the plant, through boiling. ''

Anemonoides nemorosa ''Anemonoides nemorosa'' (syn. ''Anemone nemorosa''), the wood anemone, is an early-spring flowering plant in the buttercup family Ranunculaceae, native to Europe. Other common names include windflower, European thimbleweed, and smell fox, an all ...

'' (wood anemone) is similar. Both have white flowers, are small, and are found in woody shady places. ''Anemonoides nemorosa'' however has palmately lobed leaves and does not have true petals but large sepals which are petal-like.Parnell, J. and Curtis, T. 2012. ''Webb's An Irish Flora.'' Cork University Press.

Habitat

It grows in woods and shady places in the Northern Hemisphere.

Distribution

The plant is commonly found in Great Britain and Ireland.Scannell, M.J.P. and Synnott, D.M. 1972 ''Census Catalogue of the Flora of Ireland'' Dublin Paperback. Stationery Office. ASIN: B0006CRR94 pp 127

Note

The common wood sorrel is sometimes referred to as a shamrock and given as a gift on

Saint Patrick's Day Saint Patrick's Day, or the Feast of Saint Patrick ( ga, Lá Fhéile Pádraig, lit=the Day of the Festival of Patrick), is a cultural and religious celebration held on 17 March, the traditional death date of Saint Patrick (), the foremost patr ...

. This is due to its trifoliate

clover Clover or trefoil are common names for plants of the genus ''Trifolium'' (from Latin ''tres'' 'three' + ''folium'' 'leaf'), consisting of about 300 species of flowering plants in the legume or pea family Fabaceae originating in Europe. The genus ...

-like leaf, and to early references to shamrock being eaten. Despite this, it is generally accepted that the plant described as shamrock is a species of

, usually lesser clover (''

Trifolium dubium ''Trifolium dubium'', the lesser trefoil, suckling clover, little hop clover or lesser hop trefoil, is a flowering plant in the pea and clover family Fabaceae. This species is generally accepted as the primary plant to represent the traditional ...

'').

References

External links

Den virtuella floran: ''Oxalis acetosella''

oxalis-acetosella.com — ''Oxalis acetosella''
{{Taxonbar, from=Q158576 acetosella Flora of Asia Flora of Europe Hardwood forest plants Plants described in 1753 Taxa named by Carl Linnaeus Medicinal plants Garden plants of Asia Garden plants of Europe Groundcovers