Water-thyme (Elodea canadensis, Fl. Bor.-Amer. 1: 20 (1803))

Family: Hydrocharitaceae

Author: Michx.

Bibliography: Fl. Bor.-Amer. 1: 20 (1803)

Year: 1803

Status: accepted

Rank: species

Genus: Elodea

Vegetable: False

Observations: S. Canada to U.S.A.

Description

Water-thyme, scientifically known as Elodea canadensis, is a perennial aquatic plant belonging to the family Hydrocharitaceae. Originally described in 1803 by Michx. in the Flora Boreali-Americana, this species has garnered attention for its widespread presence and its ecological significance across North America.

Water-thyme is commonly found across southern Canada and extends into the United States, where it thrives in a variety of freshwater environments. This plant typically makes its home in slow-moving or still waters, such as ponds, lakes, and ditches, where it contributes to the aquatic ecosystem by providing oxygen and habitat for small organisms.

Characterized by its long, slender stems and whorls of thin, bright green leaves, Elodea canadensis exhibits a simple yet adaptive morphology that supports its submerged lifestyle. The leaves, usually arranged in groups of three or four, have a slightly recurved appearance and are finely serrated along the edges.

The plant reproduces both vegetatively and sexually. Vegetative reproduction occurs through fragmentation, where pieces of the plant break off and develop into new individuals. Meanwhile, sexual reproduction involves small, inconspicuous flowers that emerge from the leaf axils. Although its flowers are not prominent, they play a crucial role in the plant’s propagation.

Water-thyme has significant ecological importance, acting as a key oxygenator in its native habitat. By producing oxygen through photosynthesis, it helps to maintain water quality and supports a healthy environment for aquatic life. Furthermore, it offers shelter and breeding grounds for various fish and invertebrates, fostering biodiversity within its habitat.

However, it is important to note that while Elodea canadensis is beneficial in its native regions, it can become invasive in areas outside its natural range. In some non-native locations, it has the potential to outcompete local flora, disrupt ecosystems, and hinder water flow.

Overall, Elodea canadensis exemplifies the vital role aquatic plants play in maintaining healthy freshwater ecosystems. Its presence from southern Canada to the United States highlights its adaptability and ecological significance, making it a subject of interest for both botanists and environmentalists.

Common Names

Dan: almindelig vandpest, vandpest
Eng: american waterweed, american-duckweed, broad waterweed, canada waterweed, canadian elodea, canadian pondweed, canadian waterweed, canadian waterweed/pondweed, canadian-pondweed, oxygen-weed, water-thyme, waterweed
Nld: brede waterpest, canadese waterpest
Deu: breitblättrige wasserpest, gemeine wasserpest, kanadische wasserpest
Heb: elodea canadit
Fra: elodée du canada, élodée du canada
Lav: kan, elodeja
Afr: kanadese waterpes
Lit: kanadinė elodėja
Ita: peste d’acqua comune, peste d’aqua comune
Spa: broza del canadá, oreja de gato, peste de agua
Por: elodea, espiga-de-água, estrume-novo
Hun: kanadai átokhínár
Swe: vattenpest
Ces: vodní mor kanadský
En: Water-thyme, Oxygen-weed, American-duckweed, Canadian elodea, Canadian waterweed, Canadian-pondweed, Waterweed, Schweinitz’s Waterweed, BROAD WATERWEED, CANADA WATERWEED, American Pondweed, American Waterweed, Canadian Pondweed, Canadian waterweed/pondweed, Rocky Mountain waterweed, Common elodea, Common waterweed
Af: Kanadese waterpes
Ar: أيلود كندي
Be: Эладэя канадская
Bg: Канадска водна чума
Ca: Elodea
Hr: Kanadska vodena kuga
Cs: Vodní mor kanadský
Da: Almindelig vandpest, Vandpest
Nl: Brede waterpest, Canadese waterpest
Eo: Kanada elodeo
Et: Kanada vesikatk
Fi: Kanadanvesirutto, Vesirutto
Fr: Elodée du Canada, Peste-d’eau, Élodée du Canada
De: Kanadische Wasserpest, Breitblättrige Wasserpest, Gemeine Wasserpest
He: Elodea canadit, אלודאה קנדית
Hu: Kanadai átokhínár
Is: Vatnspest
Ga: Tím uisce
It: Peste d’acqua comune, Peste d’aqua comune
Lv: Kan, Elodeja
Lt: Kanadinė elodėja
Se: Čáhcerohttu
No: Vasspest
Fa: علف مرداب
Pl: Moczarka kanadyjska
Pt: Elódea, Elódea-comum, Elodea, Espiga-de-água, Estrume-novo
Ro: Ciuma apelor
Ru: Водяная зараза, Элодея канадская
Sr: Vodena kuga
Sk: Vodomor kanadský
Es: Broza del Canadá, Oreja de gato, Peste de agua
Sv: Vattenpest, Vanlig vattenpest
Tt: Канада элодеясе
Te: ఇలోడియా కెనాడెన్సిస్
Cy: Ffugalaw Canada, Alaw Canada, Teim y Dŵr

Synonyms

• Anacharis linearis ((Rydb.) Vict.)
• Serpicula verticillata var. angustifolia (Muhl.)
• Philotria canadensis ((Michx.) Britton)
• Anacharis canadensis var. planchonii ((Casp.) Vict.)
• Elodea oblongifolia (Michx. ex Casp.)
• Udora canadensis ((Michx.) Nutt.)
• Elodea brandegeeae (H.St.John)
• Elodea planchonii (Casp.)
• Elodea occidentalis ((Pursh) H.St.John)
• Philotria iowensis (Wylie)
• Philotria linearis (Rydb.)
• Hydora canadensis ((Michx.) Besser)
• Philotria occidentalis ((Pursh) House)
• Philotria planchonii ((Casp.) Rydb.)
• Elodea canadensis var. angustifolia ((Muhl.) Farw.)
• Elodea canadensis var. planchonii ((Casp.) Farw.)
• Anacharis pomeranica (Peterm.)
• Philotria angustifolia ((Muhl.) Britton ex Rydb.)
• Anacharis planchonii ((Casp.) M.Peck)
• Apalanthe schweinitzii (Planch.)
• Serpicula occidentalis (Pursh)
• Anacharis occidentalis ((Pursh) Vict.)
• Serpicula canadensis ((Michx.) Eaton)
• Anacharis alsinastrum (Bab. ex Planch.)
• Anacharis canadensis ((Michx.) Planch.)
• Elodea latifolia (Casp.)
• Anacharis canadensis var. latifolia ((Casp.) Sanio)
• Elodea gigantea (J.K.Santos)
• Elodea iowensis (Wylie)
• Elodea ioensis (Wylie)
• Elodea schweinitzii ((Planch.) Casp.)
• Elodea linearis ((Rydb.) H.St.John)
• Elodea canadensis var. latifolia ((Casp.) Asch. & Graebn.)

Distribution

• Alabama (native)
• Arkansas (native)
• British Columbia (native)
• California (native)
• Colorado (native)
• Connecticut (native)
• Delaware (native)
• Florida (native)
• Idaho (native)
• Illinois (native)
• Indiana (native)
• Iowa (native)
• Kansas (native)
• Kentucky (native)
• Maine (native)
• Manitoba (native)
• Maryland (native)
• Masachusettes (native)
• Michigan (native)
• Minnesota (native)
• Missouri (native)
• Montana (native)
• Nebraska (native)
• Nevada (native)
• New Brunswick (native)
• New Hampshire (native)
• New Jersey (native)
• New Mexico (native)
• New York (native)
• North Carolina (native)
• North Dakota (native)
• Nova Scotia (native)
• Ohio (native)
• Ontario (native)
• Oregon (native)
• Pennsylvania (native)
• Québec (native)
• Rhode I. (native)
• Saskatchewan (native)
• South Dakota (native)
• Tennessee (native)
• Utah (native)
• Vermont (native)
• Virginia (native)
• Washington (native)
• West Virginia (native)
• Wisconsin (native)
• Wyoming (native)
• Austria (introduced)
• Baltic States (introduced)
• Belarus (introduced)
• Belgium (introduced)
• Bulgaria (introduced)
• Buryatiya (introduced)
• Canary Is. (introduced)
• Central European Rus (introduced)
• Cuba (introduced)
• Czechoslovakia (introduced)
• Denmark (introduced)
• East European Russia (introduced)
• Egypt (introduced)
• Finland (introduced)
• France (introduced)
• Germany (introduced)
• Great Britain (introduced)
• Greece (introduced)
• Hungary (introduced)
• Ireland (introduced)
• Irkutsk (introduced)
• Italy (introduced)
• Jamaica (introduced)
• Krasnoyarsk (introduced)
• Krym (introduced)
• Morocco (introduced)
• Netherlands (introduced)
• New South Wales (introduced)
• New Zealand North (introduced)
• New Zealand South (introduced)
• North European Russi (introduced)
• Northern Territory (introduced)
• Northwest European R (introduced)
• Norway (introduced)
• Palestine (introduced)
• Poland (introduced)
• Portugal (introduced)
• Puerto Rico (introduced)
• Queensland (introduced)
• Romania (introduced)
• South Australia (introduced)
• South European Russi (introduced)
• Spain (introduced)
• Sweden (introduced)
• Switzerland (introduced)
• Tasmania (introduced)
• Transcaucasus (introduced)
• Turkey (introduced)
• Turkey-in-Europe (introduced)
• Ukraine (introduced)
• Victoria (introduced)
• West Siberia (introduced)
• Western Australia (introduced)
• Yugoslavia (introduced)

Additional Images

Leaf

Taken Sep 4, 2018 by Tela Botanica − Liliane Roubaudi (cc-by-sa)

Taken Apr 19, 2020 by Nicolas Delahayes (cc-by-sa)

Taken Sep 19, 2021 by Portela-Pereira Estêvão (cc-by-sa)

Taken Jan 1, 1900 by EOL − Frank Vincentz (cc-by-sa)

Taken Oct 6, 2019 by D Weronika (cc-by-sa)

Bark

Taken Jan 1, 1800 by Tela Botanica − Thierry Pernot (cc-by-sa)

Taken Jul 13, 2018 by Jan Drnek (cc-by-sa)

Taken Jan 1, 1900 by EOL − Frank Vincentz (cc-by-sa)

Taken Sep 9, 2017 by Yoan MARTIN (cc-by-sa)

© copyright of the Board of Trustees of the Royal Botanic Gardens, Kew.

© copyright of the Board of Trustees of the Royal Botanic Gardens, Kew.

© copyright of the Board of Trustees of the Royal Botanic Gardens, Kew.

Habit

Taken Sep 3, 2018 by Tela Botanica − Liliane Roubaudi (cc-by-sa)

Taken Sep 9, 2017 by Yoan MARTIN (cc-by-sa)

Taken Jan 1, 1900 by EOL − Ondřej Zicha (cc-by-nc)

Taken Sep 3, 2018 by Tela Botanica − Liliane Roubaudi (cc-by-sa)

Taken Sep 4, 2018 by Tela Botanica − Liliane Roubaudi (cc-by-sa)

Flower

Taken Aug 15, 2019 by Photoflora – Jean-Luc TASSET (©)

Taken Sep 12, 2021 by Gail Hinds (cc-by-sa)

Taken Jun 8, 2022 by Вера Иванова (cc-by-sa)

Taken Sep 9, 2009 by EOL − Jan Ševčík (public)

Taken Oct 13, 2014 by EOL − Zoya Akulova (cc-by-nc)

Other

Taken Sep 15, 2004 by Photoflora – Jean-Luc TASSET (©)

Taken Aug 15, 2019 by Photoflora – Jean-Luc TASSET (©)

Taken Jan 1, 1970 by Photoflora – L’Abbé COSTE (©)

Taken Jul 21, 2011 by Tela Botanica − Bertrand BUI (cc-by-sa)

Taken Jul 21, 2011 by Tela Botanica − Bertrand BUI (cc-by-sa)

Fruit

Taken Jul 15, 2009 by Photoflora – Benoit BOCK (©)

Taken Oct 13, 2014 by EOL − Zoya Akulova (cc-by-nc)

Sources

• WFO (No URL)
• WFO (No URL)
• IPNI (No URL)
• GBIF (https://www.gbif.org/species/2865448)
• POWO (http://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:90075-2)
• PlantNet (https://identify.plantnet.org/species/the-plant-list/Elodea canadensis Michx.)

Specifications

Growth form: Multiple Stem

Growth habit: Forb/herb

Growth rate: Rapid

Growth

Ph maximum: 7.8

Ph minimum: 4.8

Light: 7

Atmospheric humidity: 9

Bloom months: [‘may’, ‘jun’, ‘jul’, ‘aug’]

Soil nutriments: 7