Parallel Anthology Track 73
Record label does not assign authorship, nor does www.78discography.com.
According to the Where Dead Voices Gather blog, "'Country Blues' is a variant of the song 'Darling Cora.'"
According to the wikipedia page for "Darling Cory", the earliest record of this song comes from only 1918.
There is thus not enough evidence for the copyright status of this composition to be anything other than unknown.
No public domain alternative versions found