Myriophyllum alterniflorum

Alternate-flowered Water-milfoil

LITTLE WATER MILFOIL, SLENDER 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: Alternate-flowered Water Milfoil is found in the submersed plant community. It grows in shallow water in coves of lakes or slow-moving streams.

Description: Alternate-flowered Water Milfoil is the smallest of the water-milfoils, having submersed leaves typically 1 cm long that are feather-like finely divided, arranged in whorls spaced less than 1 cm apart around the very slender stem. The tiny flowers, when present, are alternate on vertical emergent spikes, projecting less than 5 cm above the water.

Range: Alternate-flowered water-milfoil is one of the more common and widely distributed water-milfoils in Maine, and grows in all New England states, New York, Michigan, Minnesota, some Canadian Provinces, and Greenland.

Annual Cycle: Alternate-flowered water-milfoil may survive the winter as winter buds or hardy rootstalks. This plant propagates by buds and fragmentation, rarely by seeds. The tiny flowers, when present, bloom in late summer. The water milfoils are known to hybridize with each other.

Value in the Aquatic Community: Water birds eat Alternate-flowered water-milfoil, it provides shade for fish, and insect larva live among the entangled leaves and stems.

Look Alikes: Alternate-flowered water-milfoil may be confused with other water-milfoil, water marigold, coontail, common bladderwort, yellow water crowfoot, fanwort, or wermaid-weed.