''Elodea'' is a
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of eight species of
aquatic plant
Aquatic plants, also referred to as hydrophytes, are vascular plants and Non-vascular plant, non-vascular plants that have adapted to live in aquatic ecosystem, aquatic environments (marine ecosystem, saltwater or freshwater ecosystem, freshwater ...
s often called the waterweeds described as a genus in 1803. Classified in the frog's-bit family (
Hydrocharitaceae), ''Elodea'' is native to the
Americas
The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...
and is also widely used as
aquarium
An aquarium (: aquariums or aquaria) is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. fishkeeping, Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aquati ...
vegetation and laboratory demonstrations of cellular activities. It lives in fresh water. An older name for this genus is ''Anacharis'', which serves as a common name in North America.
The introduction of some species of ''Elodea'' into waterways in parts of Europe, Australia, Africa, Asia, and New Zealand has created a significant problem and it is now considered a noxious
weed
A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. Pla ...
in these areas.
;Species
# ''
Elodea bifoliata'' – Canada (
AB,
SK), W United States (
OR +
CA to
NM +
MN)
# ''
Elodea callitrichoides'' – Argentina, Uruguay
# ''
Elodea canadensis'' – most of United States + Canada
# ''
Elodea densa''
# ''
Elodea granatensis'' – much of South America
# ''
Elodea heterostemon''
# ''
Elodea najas''
# ''
Elodea nuttallii'' – much of United States + Canada
# ''
Elodea potamogeton'' – Chile, Peru, Bolivia, Ecuador
Chemical control
Chemical methods are ineffective in eradicating Elodea – at best they only slow growth for a season or two. As Elodea spreads into new ecosystems, it experiences rapid growth for 5–6 years and then slows as soil nutrients are used up. Elodea is threatening aquatic environments across Europe. Chemicals may be used in places that cause undue economic concerns, but very few aquatic herbicides are registered for aquatic use in the EU.
Fluridone, the most commonly used aquatic herbicide is highly effective against Hydrilla, but only marginally effective against Elodea, especially at lower use rates.
Mechanical control
An aquatic weed harvester collecting ''Elodea'' from a lake
The plants can also be removed from lakes and rivers mechanically. They are extracted either by hand or by using rakes, chains,
mowing boats or weed buckets. The problem is that through vegetative reproduction via fragments, mechanical removal methods can contribute to the spread of the plant. Torn fragments can be transported downstream or are introduced to new environments via attachment to boats and anchor chains.
See also
*
Stormy Lake (Alaska) a lake where Fluoridone was successfully used to eliminate elodea
*
Grass carp
The grass carp (''Ctenopharyngodon idella'') is a species of large herbivorous freshwater fish in the family Cyprinidae, native to the Pacific Far East, with a native range stretching from northern Vietnam to the Amur River on the Sino-Russian ...
also effective against elodea
References
External links
*
Jepson Manual Treatment
{{Authority control
Hydrocharitaceae
Hydrocharitaceae genera
Freshwater plants
Aquarium plants
Taxa named by André Michaux