American Bistort, Polygonum bistortoides Pursh., Family: Polygonaceae proudly displaying on the slopes of Mt. Raineer.  Edible root must be sliced and pureed with water to reduce tannin content before eating.  Roots are also good roasted after being soaked in water to reduce tannins.  Unopened flowers (bulblets) may be stripped and eaten, raw or cooked.  

Native American Uses: Roots used by Native Americans in stews, soup, served with game.  Cheyenne boiled roots with antelope and deer meat. (more).    (Another Picture)

Also see knotweeds and smartweeds.
Mountain Bistort, Polygonum bistorta L. also called Meadow Bistort leaves were preserved in seal oil by Inuit people...Or mixed with seal oil and added to stews or potherbs. Tanaina people and Inuit eat raw roots to clean teeth after eating fish eggs according to Kunklein and Turner in their book Traditional Plant Foods of Canadian Indigenous People.