Nuphar advena is a species of Nuphar

Nuphar

Nuphar is genus of aquatic plants in the family Nymphaeaceae, with a temperate to subarctic Northern Hemisphere distribution. Common names include water-lily , pond-lily, and spatterdock .A total of eight species and three hybrids are currently accepted in the genus...

native throughout the eastern United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, and just into the extreme south of Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. It is similar to the Eurasian species N. lutea

Nuphar lutea

Nuphar lutea is an aquatic plant of the family Nymphaeaceae, native to temperate regions of Europe, northwest Africa, and western Asia.-Growth:...

, and is treated as a subspecies of it by some botanists, though differing significantly in genetics.

It is locally naturalized

Naturalisation (biology)

In biology, naturalisation is any process by which a non-native organism spreads into the wild and its reproduction is sufficient to maintain its population. Such populations are said to be naturalised....

in Britain.

Medicinal and food uses

Spatterdock was long used in traditional medicine, with the root applied to the skin and/or both the root and seeds eaten for a variety of conditions. The seeds are edible, and can be ground into flour. The root is edible too, but can prove to be incredibly bitter in some plants.