In the 1940 census, here's a record for Sydney A. Fricks with wife Ruth E. Fricks of Albertville, Marshall Co., Alabama. Notice there is a sister-in-law named Eve M. Harris who is single.
"United States Census, 1940," database with images, FamilySearch(https://familysearch.org/ark:/61903/1:1:V1PD-X8P : accessed 11 August 2016), Eva M Harris in household of Sidney A Fricks, Albertville, Election Precinct 4, Marshall, Alabama, United States; citing enumeration district (ED) 48-6, sheet 10A, family 189, Sixteenth Census of the United States, 1940, NARA digital publication T627. Records of the Bureau of the Census, 1790 - 2007, RG 29. Washington, D.C.: National Archives and Records Administration, 2012, roll 60.
Here are Eve and Ruth in the 1920 census.
United States Census, 1920," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MXC5-QPN : 14 December 2015), Eva Mae Harris in household of William Harris, Moores, Blount, Alabama, United States; citing sheet 4B, NARA microfilm publication T625 (Washington D.C.: National Archives and Records Administration, n.d.); FHL microfilm 1,820,003.
So Ruth's maiden name was Harris.