Broadleaf arrowhead is an aquatic and very cold hardy plant. Grown in ponds and other water features in the home garden as well as in the wild. A common wetland plant, the wapato is also known as: broadleaf arrowhead, arrowhead, duck potato and Indian potato. The tubers of broadleaf arrowhead have long been an important food source to indigenous peoples of the Americas. The Lewis and Clark expedition depended on the plant when they were in the Columbia River basin. The seeds and tubers of are readily consumed by waterfowl, songbirds, wading birds, muskrats, and beaver.
The wapato is a perennial aquatic or marsh plant. The leaves are extremely variable very thin and are from 4” – 10” long. As can be seen by the pictures, the leaves are in the shape of arrowheads. The plants can reach heights of 3 to 4 feet.
Between mid to late summer one or two tapering cylindrical flowering stalks emerge holding 2 to 15 whorls of white, three petaled flowers with yellow reproductive parts. Each stalk is taller than the leaves. From August to October round clusters of seed casings develop. Growth peaks in July and by mid fall the emergent plant parts annually die back to the root crown.
The broadleaf arrowhead is widespread across North America, but also found natively in Hawaii, the Caribbean and the northern part of South America, broadleaf arrowhead has been introduced in Europe and Australia. As with most man made introductions, it is considered an invasive weed.
The broad-leaf arrowhead can be found along the curves of rivers, ponds and lakes, well marked by the dark green color of the leaves. The plant has strong roots and can survive through wide variations of the water level, slow currents and waves.
The roots produce white tubers covered with a purplish skin that are edible. The tubers can be dug from the ground by using your feet, a pitchfork, or a stick. Once loosened from the soil, they usually will float to the surface. Ripe tubers can be collected in the fall.
These tubers can be eaten raw or cooked for 15 to 20 minutes. The taste is similar to potatoes and chestnuts, and they can be prepared in the same fashions: roasting, frying, boiling, and so on. They can also be sliced and dried.
Picture of plant: Robert H. Mohlenbrock @ USDA-NRCS PLANTS Database / USDA NRCS. 1992. Western wetland flora: Field office guide to plant species. West Region, Sacramento.
Picture of leaf: USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner’s Sons, New York. Vol. 1: 100