Distribution: Occurring east of the Cascades in far eastern Washington; disjunct in eastern Washington, otherwise Oregon to California, also in the central and southeastern U.S.
Habitat: Shallow ponds, vernal pools, and reservoir margins.
Spores: June-October
Origin: Native
Growth Duration: Perennial
Conservation Status: Threatened in Washington (WANHP)
[none provided]
PNW Herbaria: Specimen records of Pilularia americana in the Consortium of Pacific Northwest Herbaria database.
WA Flora Checklist: Pilularia americana checklist entry.
OregonFlora: Pilularia americana information.
E-Flora BC: Pilularia americana atlas page.
CalPhotos: Pilularia americana photos.
USDA Plants: Pilularia americana information.