Northern Prairie Wildlife Research Center
|(Note that the purple spikes in the background of the photograph are those of pickerelweed (Pontederia cordata).)|
WATER PLANTAIN FAMILY (Alismataceae)
IND. STATUS: OBL
FIELD CHARACTERISTICS: A typically erect perennial with a naked stem 1-12 dm. high. The generally arrowhead-shaped leaves have great variability in width, which may be a response to varying water depths. Flowers are in whorls of 2-15 borne on the naked stem with 3 green sepals, and 3 white (or rarely pink) petals. Male flowers have many stamens. The flattened nutlets are packed into a dense head. Nutlets are 2.5-4 mm. long, winged on the margins, and have a horizontal beak 0.5-1.5(2.3) mm. long (Figure 14). The rhizomes end in an edible tuber. In flower during July and August.
|Figure 14 - Nutlets of Sagittaria|
Arrowheads (Sagittaria spp.) in general can produce arrowhead-shaped, elliptical, or ribbon-like leaves. Like the bur-reeds (Sparganium spp.), pickerelweed (Pontederia cordata), and wild celery (Vallisneria americana), the arrowheads produce submerged rosettes of ribbon-like leaves that can be distinguished from the other genera by their venation (Figure 12).
ECOLOGICAL NOTES: Broad-leaved arrowhead is a nonpersistent emergent found in shallow water and on saturated soils of marshes, shrub swamps, wooded swamps, open bogs, and stream and lake margins.
The tubers (duck potatoes) are of considerable value to wildlife. Native Americans and early European settlers collected these starchy tubers for food. Other common names for this plant are duck potato and wapato.
SOURCE: Fassett (1957); Gleason and Cronquist (1991); and Voss (1972).