At a glance
Essentials
- Size
- Stems up to 3 m or more; leaves 6–17 mm long. The range may vary with age, sex and population.
- Distribution
- Native to North America; introduced in Europe (since 1836), South America, Africa, Asia and Oceania.
- Habitat
- Shallow and deep freshwaters, rivers, lakes and channels; prefers nutrient-rich waters and sediments.
- Activity
- Rapid growth under favorable conditions; can obstruct shallow waters and channels.
- Conservation
- Considered an invasive species in many regions; included in catalogs of invasive alien species in Spain.
Observation guide
What to look for
- 01
Leaves in whorls of three (rarely two or four), oblong in shape and bright green in color.
- 02
Small flowers, white or pale purple, that float on the surface attached by long and thin scapes.
- 03
Submerged stems that can exceed 3 meters in length, with adventitious roots along the axis.
Lighting, age and viewing angle can hide features. If identification affects consumption, handling or conservation, consult specialist sources.
Ecology
Description and characteristics
Elodea canadensis is a perennial aquatic angiosperm of the family Hydrocharitaceae, native to the temperate regions of North America. It is characterized by a herbaceous and submerged habit, with stems that can reach several meters in length and leaves arranged in whorls of three, although two or four are occasionally observed. The flowers, white or pale in color, emerge to the surface via long and thin scapes; the species is dioecious, with male and female flowers on distinct plants, although in many introduced regions female specimens predominate, which limits sexual reproduction and favors vegetative propagation. This ability of asexual reproduction from stem fragments confers a high colonizing potential, being able to form dense biomass that obstructs channels and shallow waters. In lotic ecosystems, it provides habitat for invertebrates and amphibians, and its growth is influenced by the availability of nutrients and water temperature.