In seconding Gregs comments above I should point out that Rhiannon Giddens of the Choclate Drops, and Sparky both maintain that blacks did not have their "folk" contributions "stolen" from them, they let them go.

Rhiannon is very strong in the Scottish folk song community from Cape Fear, NC and calls contra dances up and down the east coast. She is very strong in dialect from Gullah to Broad Scots to Appalachian al la Elizabeth LaPrelle. About five years ago she was the featured singer at a Burns Night in Charlottesville, VA, and took the house with "Red Is The Rose".