Canada thistle and its eradication
Johnson, A.G.
Canada thistle and its eradication - U.S.A. 1912 - 1-11 p. - Purdue Agricultural Experimental Station. Circular No. 32 .
Canada thistle and its eradication - U.S.A. 1912 - 1-11 p. - Purdue Agricultural Experimental Station. Circular No. 32 .