Iris pseudacorus

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Monocots
Ordo: Asparagales

Familia: Iridaceae
Subfamilia: Iridoideae
Tribus: Irideae
Genus: Iris
Subgenus: I. subg. Limniris
Sectio: I. sect. Limniris
Series: Iris ser. Laevigatae
Species: Iris pseudacorus
Name

Iris pseudacorus L., Sp. Pl. 1: 38. 1753
Synonymy

Homotypic
Iris palustris Gaterau, Descr. Pl. Montauban: 31 (1789), nom. superfl.
Pseudo-iris palustris Medik., Hist. & Commentat. Acad. Elect. Sci. Theod.-Palat. 6: 417 (1790), nom. superfl.
Limnirion pseudacorus (L.) Opiz, Seznam 59. 1852, comb. inval.
Limniris pseudacorus (L.) Fuss, Fl. Transsilv. 636. 1866.
Xiphion pseudacorus (L.) Schrank, Fl. Monac. 1: t. 99. 1811.
Xyridion pseudacorus (L.) Klatt, Bot. Zeitung (Berlin) 30: 500. 1872.
Heterotypic
Acorus adulterinus Ludw., Herb. Blackwell.: t. 261 (1755–1757).
Iris acoriformis Boreau, Fl. Centre France ed. 3, 2: 635. 1857.
Iris acoroides Spach, Hist. Nat. Vég. 13: 44. 1846.
Iris bastardii Boreau, Fl. Centre France ed. 3, 2: 635. 1857.
Iris curtopetala Redouté, Liliac. 6: t. 340. 1811, nom. inval., pro syn.
Iris flava Tornab., Fl. Sicul. 212. 1887.
Iris lutea Ludw., Herb. Blackwell.: t. 261 (1755–1757).
Iris pallidior Hill, Brit. Herb. 47: 473. 1756.
Iris paludosa Pers., Syn. Pl. 1: 52. 1805.
Iris paludosa Mart., Fl. Mosqu. 9, 1812, nom. illeg.
Iris palustris Moench, Methodus 528. 1794, nom. illeg.
Iris palustris var. pallida Gray, Nat. Arr. Brit. Pl. 2: 196 (1821 publ. 1822).
Iris pseudacorus f. longiacuminata Prodán, Bul. Grad. Bot. Univ. Cluj 15: 67. 1935.
Iris pseudacorus f. nyaradyana Prodán in T.Savulescu, Fl. Reipubl. Popul. Roman. 11: 852. 1966.
Iris pseudacorus f. submersa Glück, Biol. Morphol. Untersuch. Wasser- Sumpfgew. 3: 13. 1911.
Iris pseudacorus subsp. acoriformis (Boreau) K.Richt., Pl. Eur. 1: 257. 1890.
Iris pseudacorus subsp. bastardii (Boreau) K.Richt., Pl. Eur. 1: 257. 1890.
Iris pseudacorus subvar. aurantiaca Druce, Rep. Bot. Exch. Club Brit. Isles 5: 53 (1917).
Iris pseudacorus var. acoroides (Spach) Baker, Handb. Irid.: 11. 1892.
Iris pseudacorus var. acoriformis (Boreau) Nyman, Consp. Fl. Eur. 702. 1882, comb. superfl.
Iris pseudacorus var. bastardii (Boreau) Nyman, Consp. Fl. Eur. 702. 1882.
Iris pseudacorus var. citrina Hook., Brit. Fl. 18. 1830.
Iris pseudacorus var. longifolia DC. in J.B.A.M.de Lamarck & A.P.de Candolle, Fl. Franç., ed. 3, 3: 237 (1805).
Iris pseudacorus var. ochroleuca Peterm., Flora 27: 344. 1844.
Iris pseudacorus var. parviflora Bastard, Ess. Fl. Maine-et-Loire, Suppl., 23. 1812.
Iris sativa Mill., Gard. Dict., ed. 8, 15. 1768.
Moraea candolleana Spreng., Syst. Veg. 1: 164. 1824.
Pseudoiris palustris Medik., Hist. & Commentat. Acad. Elect. Sci. Theod.-Palat. 6: 417 1790, nom. illeg.
Vieusseuxia iridioides Redouté, Liliac. 6: t. 340. 1811, nom. inval., pro syn.
Xiphion acoroides (Spach) Alef., Bot. Zeitung (Berlin) 21: 297. 1863.
Xyridion acoroideum (Spach) Klatt, Bot. Zeitung (Berlin) 30: 500. 1872.

Distribution
Native distribution areas:
References
Primary references

Linnaeus, C. 1753. Species Plantarum. Tomus I: 38. Reference page. 

Links

Govaerts, R. et al. 2020. Iris pseudacorus in Kew Science Plants of the World online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published online. Accessed: 2020 Aug 26. Reference page. 
USDA, ARS, Germplasm Resources Information Network. Iris pseudacorus in the Germplasm Resources Information Network (GRIN), U.S. Department of Agriculture Agricultural Research Service.

Vernacular names
العربية: سوسن شمالي كاذب
беларуская: Касач жоўты
brezhoneg: Elestr
català: Lliri groc
kaszëbsczi: Żôłti józefk
čeština: Kosatec žlutý
Cymraeg: Gellesgen gellesg
dansk: Gul Iris
Deutsch: Sumpf-Schwertlilie
English: Yellow Iris
español: Lirio amarillo
eesti: Kollane võhumõõk
euskara: Lirio hori
فارسی: پرچم زرد
suomi: Keltakurjenmiekka
Nordfriisk: Güül wüf
français: Iris des marais
Frysk: Barchjeblom
Gaeilge: Feileastram
galego: Lirio amarelo
Gaelg: Cleeshag
עברית: אירוס ענף
hrvatski: Žuta perunika
hornjoserbsce: Wódna škleńčica
magyar: Sárga nőszirom
italiano: Iris d'acqua
日本語: キショウブ
한국어: 노랑꽃창포
lietuvių: Geltonasis vilkdalgis
norsk bokmål: Sverdlilje
Nedersaksies: Pinksterbloeme
Nederlands: Gele Lis
norsk: Sverdlilje
polski: Kosaciec żółty
português: Lírio-amarelo-dos-pântanos
română: Stânjenel galben
русский: Ирис жёлтый
slovenčina: Kosatec žltý
svenska: Svärdslilja
українська: Півники болотні
中文（简体）: 黄菖蒲
中文（繁體）: 黄菖蒲
中文: 黄菖蒲

Iris pseudacorus, the yellow flag, yellow iris, or water flag, is a species of flowering plant in the family Iridaceae. It is native to Europe, western Asia and northwest Africa. Its specific epithet pseudacorus means "false acorus", referring to the similarity of its leaves to those of Acorus calamus (sweet flag), as they have a prominently veined mid-rib and sword-like shape. However, the two plants are not closely related. The flower is commonly attributed with the fleur-de-lis.

Description
Flower bud
Seeds

This herbaceous flowering perennial plant grows to 100–150 cm (39–59 in), or a rare 2 m (6 ft 7 in) tall, with erect leaves up to 90 cm (35 in) long and 3 cm (1.2 in) broad. The flowers are bright yellow, 7–10 cm (2.8–3.9 in) across, with the typical iris form. The fruit is a dry capsule 4–7 cm (1.6–2.8 in) long, containing numerous pale brown seeds.

I. pseudacorus grows best in very wet conditions, and is common in wetlands, where it tolerates submersion, low pH, and anoxic soils. The plant spreads quickly, by both rhizome and water-dispersed seed. It fills a similar niche to that of Typha and often grows with it, though usually in shallower water. While it is primarily an aquatic or marginal plant, the rhizomes can survive prolonged dry conditions.

Large I. pseudacorus stands in western Scotland form a very important feeding and breeding habitat for the endangered corncrake.

I. pseudacorus is one of two iris species native to the United Kingdom, the other being Iris foetidissima (stinking iris).

Both the petals and stem are toxic to animals and plants.[citation needed]
Nectar production

The plant was rated in second place for per day nectar production per flower in a UK plants survey conducted by the AgriLand project, which is supported by the UK Insect Pollinators Initiative. However, when number of flowers per floral unit, flower abundance, and phenology were taken into account, it dropped out of the top 10 for most nectar per unit cover per year, as did all plants that placed in the top ten, with the exception of common comfrey, Symphytum officinale.[2]
Cultivation

It is widely planted in temperate regions as an ornamental plant,[3] with several cultivars selected for bog garden planting. The following cultivars have gained the Royal Horticultural Society's Award of Garden Merit:[4]

'Roy Davidson' [5]
'Variegata' [6] (it has leaves that are edged with deep white stripes [7])

Other cultivars known include; Alba (with pale cream flowers) and Golden Fleece (with dark yellow flowers).[7]

It used to grow in the ditch of the fortified city of Mdina, on the island of Malta, where water was readily available, but since the renovation of the ditch it has since vanished from the area.[8]
Invasive species

In some regions (including the USA and South Africa)[9] where it is not native, it has escaped from cultivation to establish itself as an invasive aquatic plant which can create dense, monotypic stands, outcompeting other plants in the ecosystem. Where it is invasive, it is tough to remove on a large scale. Even ploughing the rhizomes is often ineffective. It has been banned in some areas but is still widely sold in others for use in gardens.[10]

Iris pseudacorus is reported as invasive in Connecticut, Delaware, Maryland, New Hampshire, North Carolina, Oregon, Tennessee, Virginia, Vermont, Washington, Wisconsin, and West Virginia.[11]
US Spread State/Province First Observed
IL 2009
IN 1982
MI 1932
MN 2008
NY 1882
OH 2013
PA 1954
VT 1909
WI 2005
Toxicity and uses

The plant's roots and leaves are poisonous.[12]

This plant has been used as a form of water treatment since it can take up macronutrients (such as nitrogen and phosphorus) through its roots,[13] and is featured in many AS Level Biology practicals as its ability to grow in low pH levels makes it a useful indicator.

It can also withstand high salinity levels in the water.[14]

See also

Fleur-de-lis
Flag of the Brussels-Capital Region
Iris Sawfly

References

"Iris pseudacorus L. is an accepted name". theplantlist.org (The Plant List). 23 March 2013. Retrieved 14 April 2015.
"Which flowers are the best source of nectar?". Conservation Grade. 2014-10-15. Retrieved 2017-10-18.
"RHS Plant Selector - Iris pseudacorus". Retrieved 24 June 2013.
"AGM Plants - Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 53. Retrieved 13 March 2018.
"Roy Davidson". RHS. Retrieved 25 September 2020.
"RHS Plant Selector - Iris pseudacorus 'Variegata'". Retrieved 7 September 2020.
Spencer-Jones, Rae; Cuttle, Sarah (2005). Wild Flowers of Britain and Ireland. London: Kyle Cathie Limited. p. 88. ISBN 9781856265034.
Schembri, Patrick J.; Baldacchino, Alfred E. (2011). Ilma, Blat u Hajja: Is-Sisien tal-Ambjent Naturali Malti (in Maltese). p. 81. ISBN 978-99909-44-48-8.
Mostert, Esther; Weaver, Kim (eds.). "Centre for Biological Control Annual Report 2019" (PDF). Centre for Biological Control, Rhodes University.
McIntosh, Jamie (21 June 2021). "9 Top Types of Iris for the Flower Garden". The Spruce. Retrieved 29 July 2021.
Laboratory, NOAA Great Lakes Environmental Research. "NOAA National Center for Research on Aquatic Invasive Species (NCRAIS)". nas.er.usgs.gov. Retrieved 2022-06-14.
Elias, Thomas S.; Dykeman, Peter A. (2009) [1982]. Edible Wild Plants: A North American Field Guide to Over 200 Natural Foods. New York: Sterling. p. 261. ISBN 978-1-4027-6715-9. OCLC 244766414.
Mohseni-Bandpei, A. (2010). "Nitrogen and phosphorus removal from wastewater by subsurface wetlands planted with Iris pseudacorus". Ecological Engineering. 36 (6): 777–782. doi:10.1016/j.ecoleng.2010.02.002.

Zhao, Huilin; Wang, Fen; Ji, Min (2015). "Brackish Eutrophic Water Treatment by Iris pseudacorus L.-Planted Microcosms: Physiological Responses of Iris pseudacorus L. to Salinity". International Journal of Phytoremediation. 17 (9): 814–821. doi:10.1080/15226514.2014.981240. PMID 25529785. S2CID 30542002.

Flora Europaea: Iris pseudacorus