Northern Prairie Wildlife Research Center
Aquatic and Wetland Vascular Plants of the Northern Great Plains
Wolffia Horkel -- Water-meal
Minute, thalloid, rootless plants floating at or just beneath the surface, often
abundant and forming a granular scum on the water surface, usually mixed with
other Lemnaceae; fronds flat on the upper surface (in those included
here), solitary or often paired. Reproductive pouch 1, near the base
of the frond. Flowers rare and very minute, consisting of 1 stamen (male
flower) and 1 pistil (female flower) in the pouch. Fruit globose, 1-seeded.
Reproduction mainly by budding.
These plants are the smallest of all flowering plants and are easily overlooked
in mixed culture with larger duckweeds. The tiny thalli are fairly easily
detected by their granular or mealy feel to the touch and their tendency to
adhere to the skin as the hand is withdrawn from the water.
||Fronds ellipsoid to oblong when viewed from above,
1 1/3 - 2X longer than wide, with a raised pointed apex, usually brown-punctate
||Fronds orbicular to broadly ovoid when viewed from
above, 1-1 1/3X longer than wide, not raised and pointed at the apex,
60. Lemnaceae, the Duckweed Family
3. Wolffia Horkel -- Water-meal
- 1. Wolffia borealis (Engelm.) Landolt
- 2. Wolffia columbiana Karst.
Return to Family -- Lemnaceae - The Duckweed Family
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