Myriophyllum alterniflorumDC.

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WFO wfo-0000373504 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Myriophyllum alterniflorum, photographed by Rob Foster
fig. a Rob Foster, CC BY 4.0 / 2021-09-09 / obs. 190346170
Myriophyllum alterniflorum, photographed by Antón David Pérez Rodríguez
fig. b Antón David Pérez Rodríguez, CC0 1.0 / obs. 149213676
Myriophyllum alterniflorum, photographed by Grzegorz Grzejszczak
fig. c Grzegorz Grzejszczak, CC BY-SA 4.0 / obs. 178708099
Myriophyllum alterniflorum, photographed by Rob Foster
fig. d Rob Foster, CC BY 4.0 / obs. 49555813
Myriophyllum alterniflorum, photographed by Andre Hosper
fig. e Andre Hosper, CC BY 4.0 / obs. 23276453
Myriophyllum alterniflorum, photographed by Alan Weakley
fig. f Alan Weakley, CC0 1.0 / obs. 148916700
Myriophyllum alterniflorum, photographed by Alessia Guggisberg
fig. g Alessia Guggisberg, CC BY 4.0 / obs. 189302268
Myriophyllum alterniflorum, photographed by tuohinopsakki
fig. h tuohinopsakki, CC BY 4.0 / obs. 150428091

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 55 botanical countries

Regions where Myriophyllum alterniflorum is native: Algeria, Azores, Morocco, Tunisia, China North-Central, China South-Central, China Southeast, East Aegean Is., Belarus, Belgium, Central European Russia, Corse, Czechia-Slovakia, Denmark, Finland, Føroyar, France, Germany, Great Britain, Greece, Iceland, Ireland, Italy, Netherlands, North European Russia, Northwest European Russia, Norway, Poland, Portugal, Sardegna, Sicilia, Spain, Sweden, Switzerland, Ukraine, Alaska, Connecticut, Greenland, Maine, Manitoba, Massachusetts, Michigan, Minnesota, New Brunswick, New Hampshire, New York, Newfoundland, Northwest Territories, Nova Scotia, Ontario, Québec, Rhode I., Saskatchewan, Vermont, Wisconsin AlgeriaMoroccoTunisiaChina North-CentralChina South-CentralChina SoutheastEast Aegean Is.BelarusBelgiumCentral European RussiaCorseCzechia-SlovakiaDenmarkFinlandFranceGermanyGreeceIcelandIrelandItalyNetherlandsNorth European RussiaNorthwest European RussiaNorwayPolandPortugalSiciliaSpainSwedenSwitzerlandUkraineAlaskaConnecticutGreenlandMaineManitobaMassachusettsMichiganMinnesotaNew BrunswickNew HampshireNew YorkNewfoundlandNorthwest TerritoriesNova ScotiaOntarioQuébecSaskatchewanVermontWisconsin AzoresFøroyarSardegnaRhode I.
Native distribution of Myriophyllum alterniflorum, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.
RegionTDWG codeContinent
Belarus BLR EUROPE
Belgium BGM
Central European Russia RUC
Corse COR
Czechia-Slovakia CZE
Denmark DEN
Finland FIN
Føroyar FOR
France FRA
Germany GER
Great Britain GRB
Greece GRC
Iceland ICE
Ireland IRE
Italy ITA
Netherlands NET
North European Russia RUN
Northwest European Russia RUW
Norway NOR
Poland POL
Portugal POR
Sardegna SAR
Sicilia SIC
Spain SPA
Sweden SWE
Switzerland SWI
Ukraine UKR
Alaska ASK NORTHERN AMERICA
Connecticut CNT
Greenland GNL
Maine MAI
Manitoba MAN
Massachusetts MAS
Michigan MIC
Minnesota MIN
New Brunswick NBR
New Hampshire NWH
New York NWY
Newfoundland NFL
Northwest Territories NWT
Nova Scotia NSC
Ontario ONT
Québec QUE
Rhode I. RHO
Saskatchewan SAS
Vermont VER
Wisconsin WIS
Algeria ALG AFRICA
Azores AZO
Morocco MOR
Tunisia TUN
China North-Central CHN ASIA-TEMPERATE
China South-Central CHC
China Southeast CHS
East Aegean Is. EAI

Not drawn on the map: Great Britain. We hold no public-domain boundary for this region, so it is listed rather than guessed at.

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 219 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -17.7 °C -5.6 °C 5.9 °C
Warmest month, mean daily high 15.0 °C 21.2 °C 27.7 °C
Annual rainfall 602 mm 867 mm 1,906 mm
Rainfall in the driest quarter 42 mm 150 mm 331 mm

It is found where winters are severely cold. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 219 research-grade observations of Myriophyllum alterniflorum that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 2 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Myriophyllum alterniflorum var. americanum Pugsley
  • Myriophyllum montanum Martrin-Donos

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.