Supplement to the soil survey of Alfalfa County, Oklahoma / United States Department of Agriculture, Natural Resources Conservation Service ; in cooperation with the Oklahoma Agricultural Experiment Station and the Oklahoma Conservation Commission.
Mode of access: Internet from the USDA web site. Address as of 6/18/2008: http://soildatamart.nrcs.usda.gov/Manuscripts/OK003/0/Alfalfa.pdf; current access available via PURL.
Note
Title from title screen (viewed June 18, 2008).
"Issued June 2007"--Page v.
"This supplement provides information to update the original soil survey of Alfalfa County, Oklahoma, which was issued February 1975"--Page 1.