Keywords: Piptatheropsis canadensis (as Oryzopsis canadensis) HC-1950.png en Piptatheropsis canadensis Poir Romasch P M Peterson R J Soreng captioned Oryzopsis canadensis - Canadian ricegrass 1950 http //plants usda gov/java/profile symbol PIPTA USDA-NRCS PLANTS Database / Hitchcock A S rev A Chase 1950 Manual of the grasses of the United States USDA Miscellaneous Publication No 200 Washington DC Hitchcock A S rev A Chase 1950 Manual of the grasses of the United States USDA Miscellaneous Publication No 200 Washington DC 1950 PD-USGov Uploaded with UploadWizard Piptatheropsis canadensis Manual of the grasses of the United States |