Mis-spelled word in DT version of "State of Arkansas." Should be canebrakes. A brake is a stretch of more or less swampy land, covered with one kind of plant. A very old word, found in print in this sense from the 16th century.

As I said previously mourners (moaners) was applied to the singing members in black (and often white) churches in the south, Baptist but sometimes Methodist.
"Old Coot from Tennessee" is derived from "Coon from Tennessee" (I'm Gonna Live Anyhow Until I Die) and several other titles in the collections. A lot on information in thread 22794: Coot From Tennessee
For one antecedent, go to American Memory and in Search, find "I'm Gonna Live Anyhow 'till I Die." The first line is "Now there's a coon down in Tennessee Who is as quaint as he can be."
The song has many floating verses from other songs, mostly Negro and minstrel. Mourners is from one of the floating verses.
More later.