Archaeologists have uncovered evidence that ancient Americans were cultivating gardens at least 3,800 years ago. A study published in the December 2016 issue of “Science Advances” reported that the patch of wapato – a tuber that resembles the potato – was found on ancestral lands of the Katzie people of British Columbia. This is the “first evidence,” according to the report of such gardening by the prehistoric hunter-gatherers of the region.
The researchers, led by Tanja Hoffman of Simon Fraser University, concluded that the ancient peoples of the Pacific Northwest had reformed a wetland to increase the production of the staple wild food plant. The archaeologists found that the ancient Americans had formed a rock pavement that formed a boundary for the cultivation of the spuds, which were discovered in a growing position. The wapatos, also known as Indian potatoes, were blackened and inedible. The wapatos were found in a waterlogged area that contributed to the preservation of the organic materials.
Also found at the site were approximately 150 fire-hardened wooden tool fragments, believed to have been the tips of “digging sticks.” Such remnants aid in the dating of the artifacts.
The wapato, which has a flavor which some liken to potatoes or water chestnuts, was typically harvested from October through February. The wapato was an important source of starch. The diggers found 3,768 wapato tubers. The researchers remarked in the study, “The remains were dark brown to black in color, and although only the exterior shell or skin survived on many, some also had the starchy material inside.”
In 2008, the Surrey-North Delta Leader newspaper of British Columbia reported on a 3,600-year-old native village site that was uncovered during road work for a new bridge. The evidence suggested that aboriginal people in the area were Canada’s first known farmers. An associate professor of archaeology at Simon Fraser University, Dana Lepofsky, cited it as the most significant archaeologist find to date on the mainland. The discovery of the cultivation of wapato is the oldest example of horticulture in all of Canada. “In the Pacific Northwest, there is nothing even remotely this old," Lepofsky said. "There's really nothing comparable in North America.”
The wapato, which is also known by the taxonomic name Sagittaria latifolia, is also known as arrowhead, arrowleaf, Indian potato, swamp potato and duck-potato. It was an important food source for pre-Columbian Americans throughout much of the continent.
The traditional territory of the Katzie nation included the Pitt Meadows, Pitt Polder, Pitt River, and Pitt Lake lowland areas where wapato once grew in abundance. Wapato provided the Katzie with a predictable carbohydrate balance to a largely protein diet which was based on a salmon, both these food items being predictable resources. The Katzie and their neighbors maintained relationships associated with the growing and trade of wapato which is harvested in the fall/winter months, a time of year when air and water temperatures are cold. The introduction of the common potato (Solanum tuberosum), which originated in Peru, by Europeans contributed to the rapid decline of wapato consumption.
Wapato is variously described as a marsh, semi-aquatic or aquatic herbaceous perennial with its above water foliage having leaves having a characteristic arrowhead shape (Borman et al 1997; Brayshaw 1985; Pojar and MacKinnon 1996). It is a member of the Alismataceae or Water Plantain family. The plant produces walnut to golf-ball size tubers at the bottom of ponds, lakes, and streams. The starchy tubers are storage organs produced from the plants' horizontally creeping underground stems or rhizomes. "Wapato" is the Chinook jargon for both the native tuber and the common potato.