Arrowhead

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Arrowhead leaves

Arrowhead flower

Arrowhead staminate and pistillate flowers

Arrowhead inflorescence and leaf

Arrowhead habit

Arrowhead leaves

Arrowhead

Arrowhead leaf

Arrowhead habit

Arrowhead inflorescence with lower pistillate flowers in bloom

Arrowhead

Morphology

Stem

Flowering stalks up to 48 inches tall arise from tuberous rootstocks buried in the mud.

Leaves

Variable, on long, erect stalks up to 60 inches long; blades to 20 inches long; mostly arrowhead-shaped, prominently nerved; apex and basal lobes triangular to long and narrow, basal lobes parallel to widely divergent. In broad blades, the basal lobes are somewhat shorter than the terminal lobe but are longer than the terminal lobe in narrow blades.

Inflorescence

Flowers in whorls of 3; whorls 2-15, on slender, erect flowering stalks that often exceed the leaves; upper whorls staminate, flowers on short stalks; lower whorls pistillate, flowers on longer, sometimes ascending stalks; pistillate flowers bloom before staminate; whorls subtended by bracts; bracts 3, boat-shaped, to .6 inch long, papery, blunt or pointed.

Flower

Sepals 3, to .4 inch long, green, reflexed in fruit; petals 3, about .8 inch long, showy, white; stamens and pistils on a convex receptacle; stamens 20-40; filaments slender, linear, glabrous; anthers oblong.

Fruit

Achene, obovate, to 1/6 inch long, beaked, margins winged, faces without wings or sharp ridges; seeds horseshoe-shaped. Fruits in spherical heads to 1.5 inch across.

Ecology

Habitat

In shallow water; slow streams, shorelines of lakes and ponds, marshes, and ditches.

Distribution

Throughout Kansas.

Practical Information

Uses

Several prairie tribes ate the potato-like tubers boiled or roasted. The Lewis and Clark expedition recorded in their journal that they were fed roasted Sagittaria rootstocks by Native Americans in the Northwest. Native Americans steeped the roots and took the tea for indigestion and used a tea from the plant to treat rheumatism.