Elodea

Elodea canadensis · Aquatic plants

Up close · Photo: Евгений Маринкин / CC BY

NativeSubmerged

Also called Canada waterweed, Anacharis, Common waterweed (elodea), Common elodea

How to identify Elodea

Small, oblong leaves usually in whorls of 3
Leaves about 1/4 to 1/2 inch long with rounded tips
Tiny white flowers float at the surface on threadlike stalks

Similar plants

Western waterweed has narrower, pointed, often curled leaves; Brazilian elodea and hydrilla have whorls of 4 or more larger leaves.

Growth profile

Growing season	Stays green under ice, grows strongly in late spring, peaks in early to mid summer and may thin out by late summer.
Starts growing	About 40 to 50 F water; grows in low light
Light	Tolerates low light and moderate turbidity
Depth	1 to 15 feet, occasionally to 30 feet in clear water
How it spreads	Stem fragments and dense winter shoot tips; seeds rare
Habitat	Lakes, ponds, canals and slow streams, from clear to nutrient rich water over soft bottoms.

Why it matters in a lake

Can form dense beds that reach the surface in ponds and canals. Fragments root easily, and beds often crash and decay in late summer, which can lower oxygen.