Aquatic and Wetland Vascular Plants of the Northern Great Plains
60. Lemnaceae, the Duckweed Family
1. Lemna L. -- Duckweed3. Lemna minor L.
Fronds nearly orbicular to elliptic-obovate, broadest near the middle, 2-4 mm long, symmetric or nearly so, green to yellowish-green, never red-tinged or mottled on either surface, obscurely 3(-5)-nerved, when 4- to 5-nerved (rare) the lateral nerves arising near the base of the inner ones; both surfaces flat to weakly convex, the upper surface with a low papilla at the apex and often one above the node, usually with a low median ridge or row of smaller papillae between them, the lower surface never inflated, with air spaces in 2 layers but these less than 0.3 mm in diameter. Turions not produced. Root sheath not winged, root tip rounded. Fruit ovoid to ellipsoid, wingless, 1-seeded. Frequent, s SD and NE, possibly rare in e SD; (Cool regions of N.Amer., Europe, Africa, Australia and all but eastern Asia, absent from S.Amer.).
In this region, L. minor may be limited relative to L. turionifera
by its inability to form turions. The few collections we have from s SD come
from waters kept warm through the winter by active springs.
Previous Section -- Lemna gibba L.
Return to Family -- Lemnaceae - The Duckweed Family
Next Section -- Lemna minuscula Herter
