Swamps, ditches, shores. Holmberg - Map . Wet sandy soils, swamps, wet woods. Swamps, shores, meadows. Hitchcock - Map .
Shallow water sloughs in meadows.
Siliceous rock and dry peat at high altitudes. Meadows, shores, salt marshes. Linnaeus - Velvet Grass Map . Meadows, roadsides, sterile fields. Roadsides, railroads, salt marshes, beaches.