Alismataceae: Arrowhead Family
This is a family that contains approximately 15 genera and 85 species (Carr); small by comparison. However, it plays a large role in certain aquatic habitats. Burheads, Sagittaria species, and Water Plantain are the most prolific species. They are common in shallow areas around the edges of lakes as emergent aquatic plants. Most species also have an edible underground bulb that is very starchy which can be used for food.
Aquatic plants in this family have played a major role in filling the aquatic habitats that have been created by new dams. In north america, different arrowhead species and burrheads have been utilized by the army corp of engineers for watershed improvement. These plants decrease the amount of light that penetrates the water column to feed algae. It also acts as a refuge for fish and other important aquatic animals. See aquatic research by LAERF
Systematics: Aquatic herbs with milky sap. They are monocots, yet very similar taxonomically to magnolieds. They have many separate stamen and many separate pistils. 3 petals alternate with 3 sepals. The fruits are achenes. Ovaries superior. Leaves alternate, simple and sheathing at the base.
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