Wetland Plants of Wisconsin

Wolffia borealis (Engelm. ex Hegelm.) Landolt
northern water-meal
Wolffia borealis

Individuals of water-meal are called fronds. Each frond of W. borealis consists of a small, green, floating body (0.7-1.5 mm long!) with no roots. Members of this genus (11 species, 5 in North America) are believed to be the smallest angiosperm plants. Water meal does best in full sun and in nutrient rich water. Under those conditions they can grow rapidly, reproducing not by seeds usually, but by simple division of a frond to produce a new "daughter" frond. Northern water-meal plants rarely flower.

Identification of the species of water-meal can be difficult. A good source of information can be found in the book: Flora of North America Editorial Committee, eds. 2000. Flora of North America North of Mexico. Vol. 22. Magnoliophyta: Alismatidae, Arecidae, Commelinidae (in part), and Zingiberidae. Oxford University Press. pp143-153. It can also be found on the web at this site.


known Wisconsin distribution


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