Myriophyllum humile

Low Water-milfoil

NATIVE TO MAINE

NOTE: All leafy milfoils display a wide range of vegetative variability. All milfoils found in Maine waters should be considered “suspect” as potential invaders until a positive identification has been confirmed.

Habitat: Low water-milfoil is found in the submersed plant community. It can grow in shallow water in coves of lakes or slow-moving streams.

Description: Low water-milfoil has submersed leaves only. The leaves are feather-like finely, divided and are typically closely spaced along the stem in an alternate or “irregularly scattered” arrangement. Stems and/or leaves may be reddish. Unlike all of invasive milfoils on Maine’s watch-list, and most of the other Maine native milfoils, low water-milfoil does not produce flowers on an emergent stalk. Low water-milfoil and its close native look-alike, Farwell’s water-milfoil, both produce flowers, followed by small fruits, along the submersed stems in the leaf axils. The tiny fruits of low water-milfoil are comprised of four smooth-sided sections (as opposed to the bumpy ridged fruits of Farwell’s water-milfoil). Low water-milfoil does not form winter buds. (Farwell’s does produce winter buds.)

Range: Low water-milfoil is a native plant, relatively rare in Maine, scattered in northern New England states, Nova Scotia, common in southern New England, west to Minnesota, south to Maryland.

Annual Cycle: Low water-milfoil may survive the winter as hardy rootstalks. This plant propagates by fragmentation and by seeds. Some water milfoils are known to hybridize with each other.

Value in the Aquatic Community: Low water-milfoil is food source for wildlife including water fowl. The plants provide shade and cover for fish and insect larva.

Look Alikes: May be confused with other water-milfoil species (especially Farwell’s water-milfoil), coontail, and the submerged forms of water marigold, common bladderwort, white water crowfoot, yellow water crowfoot, fanwort, prickly hornwort, or mermaid-weed.