[7][8] It is commonly found in shallow muddy ponds from northern Alaska and Yukon southward to central California and northern New Mexico, and can be recognized easily by its large floating leaves and bright yellow blossoms.

Nuphar polysepala is a perennial,[5] rhizomatous, aquatic[2] herb[6][5] with spongy, creeping, branching,[9] up to 5 m long,[10] and 3-8 cm wide rhizomes[7] and an extensive root system.

[13][14] The solitary, pedunculate, bisexual,[13] 5–10 cm wide flowers[7] float on the water surface, or extend beyond it.

[1] The seeds are edible; they pop like popcorn, and can be steamed as a vegetable, dried and ground for flour, or can be cooked like oatmeal.

The rootstock infusion is used as a traditional gargle for mouth, sore throats and douche for vaginal inflammation.