imported>Randy Kryn: /* As food */ uppercase per alternate name at direct link (Andes Mountains)

2025-10-09T11:55:48Z

As food: uppercase per alternate name at direct link (Andes Mountains)

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{{Short description|Genus of flowering plants}}
{{Other uses}}
{{Automatic taxobox
|image=Oxalis acetosella jfg.jpg
|image_caption=Common wood-sorrel (''[[Oxalis acetosella]]''), the type species of the genus
|taxon=Oxalis
|authority=[[Carl Linnaeus|L.]]
|subdivision_ranks=[[Species]]
|subdivision=About 550, see [[List of Oxalis species|List of ''Oxalis'' species]]
}}

'''''Oxalis''''' ({{IPAc-en|ɒ|k|s|'|ɑː|l|ᵻ|s}} (British English)<ref>{{Cite web |url=https://www.lexico.com/en/definition/oxalis |title=Oxalis | Definition of Oxalis by Oxford Dictionary on Lexico.com also meaning of Oxalis |website=Lexico Dictionaries | English |access-date=2019-06-12 |archive-date=2021-06-12 |archive-url=https://web.archive.org/web/20210612062538/https://www.lexico.com/en/definition/oxalis |url-status=dead }}</ref> or {{IPAc-en|ˈ|ɒ|k|s|ə|l|ᵻ|s}} (American English)<ref>''Sunset Western Garden Book'' 1995:606–607</ref>) is a large [[genus]] of [[flowering plant]]s in the wood-sorrel family, [[Oxalidaceae]], comprising over 550 species.<ref name="Christenhusz-Byng2016">{{cite journal |author1=Christenhusz, M. J. M. |author2=Byng, J. W. |year=2016 |title=The number of known plants species in the world and its annual increase |journal=Phytotaxa |volume=261 |pages=201–217 |url=http://biotaxa.org/Phytotaxa/article/download/phytotaxa.261.3.1/20598 |doi=10.11646/phytotaxa.261.3.1 |issue=3 |doi-access=free |bibcode=2016Phytx.261..201C |access-date=2017-12-21 |archive-date=2016-07-29 |archive-url=https://web.archive.org/web/20160729085754/http://biotaxa.org/Phytotaxa/article/download/phytotaxa.261.3.1/20598 |url-status=live }}</ref> The genus occurs throughout most of the world, except for the [[Polar region|polar]] areas; species diversity is particularly rich in tropical [[Brazil]], [[Mexico]], and [[South Africa]].

Many of the species are known as '''wood-sorrels'''<ref>{{cite web | title=Wood-sorrel ''Oxalis acetosella'' L. | website=PlantAtlas | url=https://plantatlas2020.org/atlas/2cd4p9h.cba | access-date=2025-06-13}}</ref> (also as '''wood sorrels''' or '''woodsorrels''') as they have an acidic taste reminiscent of the sorrel proper (''[[Rumex acetosa]]''), which is not closely related. Some species are called '''yellow sorrels''' or '''pink sorrels''' after the colour of their flowers instead. Other species are colloquially known as '''false [[shamrock]]s''', and some called '''[[sourgrass]]es'''. For the genus as a whole, the term '''oxalises''' is also used.

==Description==
[[File:Oxalis floral diagram.jpg|thumb|[[Floral diagram]] of ''Oxalis'']]
The plants are [[annual plant|annual]] or [[perennial]]. The leaves are divided into three to ten or more obovate and top-notched leaflets, arranged palmately with all the leaflets of roughly equal size. The majority of species have three leaflets, superficially similar to those of some [[clover]]s.<ref>{{Cite web |url=https://plants.ces.ncsu.edu/plants/all/oxalis/ |title=Oxalis |website=NC State University |access-date=2018-09-20 |archive-date=2021-09-01 |archive-url=https://web.archive.org/web/20210901071510/https://plants.ces.ncsu.edu/plants/oxalis/ |url-status=live }}</ref> Some species exhibit rapid changes in leaf angle in response to temporarily high light intensity to decrease [[photoinhibition]].<ref>{{Cite journal |title=Photosynthesis and photoinhibition in two differently coloured varieties of ''Oxalis triangularis'' — the effect of anthocyanin content |journal=Photosynthetica |volume=49 |issue=3 |pages=346–352 |last=S. L. Nielsen, A. M. Simonsen |date=September 2011 |doi=10.1007/s11099-011-0042-y |s2cid=24583290|doi-access=free |bibcode=2011Phsyn..49.0042N }}</ref>

The flowers have five petals, which are usually fused at the base, and ten [[stamen]]s. The petal colour varies from white to pink, red or yellow;<ref>{{Cite web |url=https://wimastergardener.org/article/shamrocks-oxalis-spp/ |title=Shamrocks, Oxalis spp. |last=Mahr |first=Susan |date=March 2009 |website=Master Gardener Program University of Wisconsin-Extension |access-date=2018-09-20 |archive-date=2018-09-21 |archive-url=https://web.archive.org/web/20180921034823/https://wimastergardener.org/article/shamrocks-oxalis-spp/ |url-status=live }}</ref> [[anthocyanin]]s and [[xanthophyll]]s may be present or absent but are generally not both present together in significant quantities, meaning that few wood-sorrels have bright orange flowers. The fruit is a small [[Capsule (fruit)|capsule]] containing several seeds. The roots are often tuberous and succulent, and several species also  reproduce vegetatively by production of [[bulbil]]s, which detach to produce new plants.

== Ecology ==
[[Image:TAU-2013-Oxalis 0039a-ZachiEvenor.jpg|thumb|''[[Oxalis pes-caprae]]'']]
[[File:Lyc oviposit.jpg|thumb|right|Pale grass blue (''[[Pseudozizeeria maha]]'') of the dry-season brood laying eggs on ''Oxalis'']]
Several ''Oxalis'' species dominate the plant life in local woodland ecosystems, be it [[Coast Range (EPA ecoregion)|Coast Range ecoregion]] of the [[North America]]n [[Pacific Northwest]], or the [[Sydney Turpentine-Ironbark Forest]] in southeastern Australia where least yellow sorrel (''[[Oxalis exilis|O. exilis]]'') is common. In the United Kingdom and neighboring Europe, common wood sorrel (''[[Oxalis acetosella|O. acetosella]]'') is the typical woodland member of this genus, forming large swaths in the typical mixed deciduous forests dominated by downy birch (''[[Betula pubescens]]'') and sessile oak (''[[Quercus petraea]]''), by sycamore maple (''[[Acer pseudoplatanus]]''), [[Bracken|common bracken]] (''Pteridium aquilinum''), pedunculate oak (''[[Quercus robur|Q. robur]]'') and [[blackberries]] (''Rubus fruticosus'' agg.), or by common ash (''[[Fraxinus excelsior]]''), [[dog's mercury]] (''Mercurialis perennis'') and European rowan (''[[Sorbus aucuparia]]''); it is also common in woods of common juniper (''[[Juniperus communis]]'' ssp. ''communis''). Some species – notably [[Oxalis pes-caprae|Bermuda-buttercup]] (''O. pes-caprae'') and [[Oxalis corniculata|creeping woodsorrel]] (''O. corniculata'') – are pernicious, invasive weeds when escaping from cultivation outside their native ranges; the ability of most wood-sorrels to store reserve energy in their tubers makes them quite resistant to most weed control techniques.

A 2019 study<ref>{{Cite journal |last1=Jooste |first1=Michelle |last2=Roets |first2=Francois |last3=Midgley |first3=Guy F. |last4=Oberlander |first4=Kenneth C. |last5=Dreyer |first5=Léanne L. |date=2019-10-23 |title=Nitrogen-fixing bacteria and Oxalis – evidence for a vertically inherited bacterial symbiosis |journal=BMC Plant Biology |volume=19 |issue=1 |pages=441 |doi=10.1186/s12870-019-2049-7 |issn=1471-2229 |pmc=6806586 |pmid=31646970 |doi-access=free |bibcode=2019BMCPB..19..441J }}</ref> suggested that species from this [[genus]] have a symbiotic relationship with nitrogen fixing [[Bacillus|''Bacillus'' endophytes]], storing them in plant tissues and seeds, which could explain its ability to spread rapidly even in poor soils.

Tuberous woodsorrels provide food for certain small [[herbivore]]s, such as the [[Montezuma quail]] (''Cyrtonyx montezumae''). The foliage is eaten by some [[Lepidoptera]], such as the [[Polyommatini]] [[pale grass blue]] (''Pseudozizeeria maha''), which feeds on creeping wood sorrel and others, and [[Zizeeria lysimon|dark grass blue]] (''Zizeeria lysimon'').

''Oxalis'' species are susceptible to the [[rust (fungus)|rust fungus]] (''[[Puccinia oxalidis]]'').

[[File:Close-up of an 'apricot' NZ yam.JPG|thumb|Tubers of oca (''[[Oxalis tuberosa]]'') for eating]]
[[File:Oxalis tetraphylla leaves.jpg|thumb|right|Four-leaved pink-sorrel (''[[Oxalis tetraphylla]]'') ]]

==Uses==

===As food===
Several species of ''Oxalis'' are edible wild plants that have been consumed by humans around the world for millennia.<ref name="autogenerated2">{{Cite book |last=Duke |first=James A. |url=https://books.google.com/books?id=rVrteo-8cI0C |title=Handbook of Edible Weeds: Herbal Reference Library |date=2000-11-10 |publisher=CRC Press |isbn=978-0-8493-2946-3 |language=en}}</ref> In Dr. James Duke's ''Handbook of Edible Weeds'', he notes that the Native American [[Kiowa]] people chewed wood sorrel to alleviate thirst on long trips, the [[Potawatomi]] cooked it with sugar to make a dessert, the [[Algonquin people|Algonquin]] considered it an [[aphrodisiac]], the Cherokee ate wood sorrel to alleviate mouth sores and a sore throat, and the [[Iroquois]] ate wood sorrel to help with cramps, fever and nausea.<ref name="autogenerated2" />

The fleshy, juicy edible [[tuber]]s of the [[Oxalis tuberosa|oca]] (''O. tuberosa'') have long been cultivated for food in [[Colombia]] and elsewhere in the northern [[Andes Mountains]] of [[South America]]. It is grown and sold in [[New Zealand]] as "New Zealand yam" (although not a true yam), and varieties are now available in yellow, orange, apricot, and pink, as well as the traditional red-orange.<ref>{{Cite web |url=https://www.vegetables.co.nz/vegetables-a-z/yams/ |title=Yams |website=Vegetables |access-date=2021-01-17 |archive-date=2021-01-20 |archive-url=https://web.archive.org/web/20210120073510/https://www.vegetables.co.nz/vegetables-a-z/yams/ |url-status=live }}</ref>

The leaves of scurvy-grass sorrel (''O. enneaphylla'') were eaten by [[sailor]]s travelling around [[Patagonia]] as a source of [[vitamin C]] to avoid [[scurvy]].

In [[India]], creeping wood sorrel (''O. corniculata'') is eaten only seasonally, starting in December–January. The [[Bodo people|Bodos]] of north east India sometimes prepare a sour fish curry with its leaves. The leaves of common wood-sorrel (''[[Oxalis acetosella|O. acetosella]]'') may be used to make a lemony-tasting tea when dried.

===Other uses===
[[File:Oxalis versicolor (candycane sorrel).jpg|thumb|right|''[[Oxalis versicolor]]'' (candycane sorrel) grown in New Zealand]]

In the past, it was a practice to extract crystals of [[calcium oxalate]] for use in treating diseases and as a [[Salt (chemistry)|salt]] called ''sal acetosella'' or [[Potassium hydrogenoxalate|"sorrel salt"]] (also known as "salt of lemon"). Growing oca tuber [[root cap]]s are covered in a [[fluorescent]] slush rich in [[harmaline]] and [[harmine]] which apparently suppresses [[Pest (organism)|pest]]s.<ref>Bais ''et al.'' (2002, 2003)</ref>

==As ornamental plants==
[[File:Dreieckiger Glücksklee (Oxalis triangularis) (19067830888).jpg|thumb|''[[Oxalis triangularis]]'']]
Several species are grown as [[pot plant]]s or as [[ornamental plant]]s in [[garden]]s, for example, ''O. versicolor''.

''Oxalis'' flowers range in colour from whites to yellow, peaches, pink, or multi-coloured flowers.<ref>{{Cite web|url=http://www.stuff.co.nz/nelson-mail/lifestyle-entertainment/lifestyle/home-and-garden/2495449/A-daring-passion|title=A daring passion|date=28 August 2009|access-date=25 July 2014|archive-date=27 July 2014|archive-url=https://web.archive.org/web/20140727203727/http://www.stuff.co.nz/nelson-mail/lifestyle-entertainment/lifestyle/home-and-garden/2495449/A-daring-passion|url-status=live}}</ref>

Some varieties have double flowers, for example the double form of ''O. compressus''. Some varieties are grown for their foliage, such as the dark purple-leaved ''O. triangularis''.

Species with four regular leaflets, in particular ''[[Oxalis tetraphylla|O. tetraphylla]]'' (four-leaved pink-sorrel), are sometimes misleadingly sold as "four-leaf [[clover]]", taking advantage of the mystical status of [[four-leaf clover]].

==Selected species==
{{Main|List of Oxalis species|l1=List of ''Oxalis'' species}}
* ''[[Oxalis acetosella]]'' – common wood-sorrel
* ''[[Oxalis adenophylla]]'' – Chilean oxalis, silver shamrock
* ''[[Oxalis albicans]]'' – hairy woodsorrel, white oxalis, radishroot woodsorrel, radishroot yellow-sorrel, California yellow-sorrel
* ''[[Oxalis alpina]]'' – alpine sorrel
* ''[[Oxalis ambigua]]''
* ''[[Oxalis articulata]]'' Savign. – pink-sorrel
* ''[[Oxalis ausensis]]''
* ''[[Oxalis barrelieri]]'' – lavender sorrel
* ''[[Oxalis bowiei]]'' – Bowie's wood-sorrel, Cape shamrock
* ''[[Oxalis brasiliensis]]'' – Brazilian woodsorrel
* ''[[Oxalis caerulea]]'' – blue woodsorrel
* ''[[Oxalis caprina]]''
* ''[[Oxalis corniculata]]'' – creeping wood sorrel, procumbent yellow-sorrel, sleeping beauty, ''chichoda bhaji'' (India)
* ''[[Oxalis debilis]]'' Kunth
* ''[[Oxalis decaphylla]]'' – ten-leaved pink-sorrel, tenleaf wood sorrel
* ''[[Oxalis dehradunensis]]''
* ''[[Oxalis depressa]]''
* ''[[Oxalis dichondrifolia]]'' – peonyleaf wood sorrel
* ''[[Oxalis dillenii]]'' Jacquin – southern yellow woodsorrel, Dillen's woodsorrel, Sussex yellow-sorrel
* ''[[Oxalis drummondii]]'' – Drummond's woodsorrel, chevron oxalis
* ''[[Oxalis ecuadorensis]]''
* ''[[Oxalis enneaphylla]]'' – scurvy-grass sorrel
* ''[[Oxalis exilis]]'' – least yellow-sorrel
* ''[[Oxalis frutescens]]'' – shrubby wood-sorrel
* ''[[Oxalis gigantea]]''
* ''[[Oxalis glabra]]'' – finger-leaf
* ''[[Oxalis grandis]]'' – great yellow-sorrel, large yellow woodsorrel
* ''[[Oxalis griffithii]]'' Edgew. & Hook.f.
* ''[[Oxalis hedysaroides]]'' – fire fern
* ''[[Oxalis hirta]]'' – hairy sorrel
* ''[[Oxalis illinoensis]]'' – Illinois wood-sorrel
* ''[[Oxalis inaequalis]]''
* ''[[Oxalis incarnata]]'' L. – pale pink-sorrel
* ''[[Oxalis lasiandra]]'' – Mexican shamrock
* ''[[Oxalis latifolia]]'' Kunth – garden pink-sorrel
* ''[[Oxalis luederitzii]]''
* ''[[Oxalis luteola]]'' Jacq.
* ''[[Oxalis magellanica]]'' G.Forst.
* ''[[Oxalis magnifica]]'' Kunth – snowdrop wood-sorrel
* ''[[Oxalis massoniana]]''
* ''[[Oxalis megalorrhiza]]'' – fleshy yellow-sorrel
* ''[[Oxalis melanosticta]]''
* ''[[Oxalis micrantha]]'' – dwarf woodsorrel
* ''[[Oxalis montana]]'' – mountain woodsorrel, white woodsorrel
* ''[[Oxalis nelsonii]]'' – Nelson's sorrel
* ''[[Oxalis norlindiana]]''
* ''[[Oxalis obliquifolia]]''
* ''[[Oxalis oregana]]'' – redwood sorrel, Oregon sorrel
* ''[[Oxalis ortgiesii]]'' Regel – fishtail oxalis
* ''[[Oxalis pennelliana]]''
* ''[[Oxalis pes-caprae]]'' – Bermuda-buttercup, African wood-sorrel, Bermuda sorrel, buttercup oxalis, Cape sorrel, English weed, soursob, "[[goat's-foot]]", "[[sourgrass]]", soursop (not to be confused with [[soursop|the fruit of that name]])
* ''[[Oxalis priceae]]'' – tufted yellow-sorrel
* ''[[Oxalis pulchella]]''
* ''[[Oxalis purpurea]]'' L. – purple wood-sorrel
* ''[[Oxalis rosea]]'' Feuillée ex Jacq. – annual pink-sorrel
* ''[[Oxalis rubra]]'' A.St.-Hil. – red wood-sorrel
* ''[[Oxalis rufescens]]''
* ''[[Oxalis rugeliana]]'' – coamo
* ''[[Oxalis rusciformis]]''
* ''[[Oxalis schaeferi]]''
* ''[[Oxalis spiralis]]'' – spiral sorrel, volcanic sorrel, velvet oxalis
* ''[[Oxalis stricta]]'' – common yellow woodsorrel, common yellow oxalis, upright yellow-sorrel, lemon clover, "[[pickle plant]]", "[[sourgrass]], "yellow woodsorrel"
* ''[[Oxalis suksdorfii]]'' – western yellow woodsorrel, western yellow oxalis
* ''[[Oxalis tenuifolia]]'' – thinleaf sorrel
* ''[[Oxalis tetraphylla]]'' – four-leaved pink-sorrel, four-leaf sorrel, [[Iron Cross]] oxalis, "[[lucky clover]]"
* ''[[Oxalis triangularis]]'' – threeleaf purple shamrock
* ''[[Oxalis trilliifolia]]'' – great oxalis, threeleaf woodsorrel
* ''[[Oxalis tuberosa]]'' – oca, oka, New Zealand yam
* ''[[Oxalis valdiviensis]]'' – Chilean yellow-sorrel
* ''[[Oxalis virginea]]'' – virgin wood-sorrel
* ''[[Oxalis versicolor]]'' – candycane sorrel
* ''[[Oxalis violacea]]'' – violet wood-sorrel
* ''[[Oxalis vulcanicola]]'' – volcanic sorrel or velvet oxalis<ref>{{Cite web |url=https://plants.usda.gov/java/ClassificationServlet?source=profile&symbol=OXALI&display=31 |title=Classification | USDA PLANTS |website=plants.usda.gov |access-date=2021-01-17 |archive-date=2021-01-17 |archive-url=https://web.archive.org/web/20210117034413/https://www.plants.usda.gov/java/ClassificationServlet?source=profile&symbol=OXALI&display=31 |url-status=live }}</ref><ref>{{Cite web |url=http://www.guynesom.com/CorniculataeSidoid09.pdf |title=Again: Taxonomy Of Yellow-Flowered Caulescent Oxalis (Oxalidaceae) In Eastern North America J. Bot. Res. Inst. Texas 3(2): 727 – 738. 2009 |access-date=2013-10-24 |archive-date=2013-10-29 |archive-url=https://web.archive.org/web/20131029185115/http://www.guynesom.com/CorniculataeSidoid09.pdf |url-status=live }}</ref>

<gallery>
(MHNT) Oxalis articulata - Habit.jpg|''[[Oxalis articulata]]'' Savign. subsp. ''rubra'' (A.St.-Hil.)
Oxalis corymbosa 2.jpg|''[[Oxalis debilis]]'' Kunth (syn. ''O. corymbosa'')
Oxalis dehradunensis (Dun Ambushi) in Hyderabad, AP W IMG 9725.jpg|''[[Oxalis dehradunensis]]'' Raizada, 1976
Oxalis gigantea 1.jpg|''[[Oxalis gigantea]]'' Barneoud, 1846
Oxalis luteola 1.jpg|''[[Oxalis luteola]]''
Oxalis magnifica 2.jpg|''[[Oxalis magnifica]]'' R.Knuth, 1919
Oxalis priceae.jpg|''[[Oxalis priceae]]'' [[John Kunkel Small|Small]]
Oxalis purpurea (Habitus) 2.jpg|''[[Oxalis purpurea]]'' L., 1753
</gallery>

==References==
{{Reflist|2}}

==Further reading==

* Bais, Harsh Pal; Vepachedu, Ramarao & Vivanco, Jorge M. (2003): Root specific elicitation and exudation of fluorescent β-carbolines in transformed root cultures of ''Oxalis tuberosa. Plant Physiology and Biochemistry'' '''41'''(4): 345–353. {{doi|10.1016/S0981-9428(03)00029-9}} [https://web.archive.org/web/20080905145156/http://lamar.colostate.edu/~jvivanco/papers/PPB/2003.pdf Preprint PDF fulltext]
* Łuczaj, Łukasz (2008): Archival data on wild food plants used in Poland in 1948. ''Journal of Ethnobiology and Ethnomedicine'' '''4''': 4. {{doi|10.1186/1746-4269-4-4|doi-access=free}} [http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=2275233&blobtype=pdf PDF fulltext]{{dead link|date=July 2025|bot=medic}}{{cbignore|bot=medic}}

{{Taxonbar|from=Q157378}}
{{Authority control}}

[[Category:Oxalis| ]]
[[Category:Oxalidales genera]]

Oxalis - Revision history

imported>Randy Kryn: /* As food */ uppercase per alternate name at direct link (Andes Mountains)