Iowa , Kansas , Manitoba , Minnesota , Missouri , Montana , Nebraska , North Dakota , Oklahoma , Saskatchewan , South Dakota , Wyoming
[1]
Bull. Soc. Bot. France 48: xvi (1902)
[2]
Bull. Torrey Bot. Club 40: 53 (1913)
[3]
Bull. Torrey Bot. Club 34: 422 (1907)
[4]
Just's Bot. Jahresber. 27(1): 496 (1901)
[5]
Bull. Soc. Bot. France 48: xvii (1902)
[6]
J.Torrey & A.Gray, Fl. N. Amer. 1: 340 (1838)
[7]
Syst. Veg., ed. 16. 3: 308 (1826)
[8]
Unknown
[9]
Proc. Biol. Soc. Washington 18: 13 (1905)
[10]
Bull. Leeds Herb. 2: 6 (1908)
[11]
Bull. Soc. Bot. France 48: xvii (1901)
[12]
Publ. Sci. Univ. Wyoming, Bot. 1: 118 (1926)
[13]
Erythea 7: 64 (1899)
[14]
Proc. Biol. Soc. Washington 18: 14 (1905)
[15]
Publ. Sci. Univ. Wyoming, Bot. 1: 115 (1926)
[16]
Publ. Sci. Univ. Wyoming, Bot. 1: 116 (1926)