As Geoff the Duck has pointed out, it depends whether it's being sung or murdered....

The Prickly Bush (although Spiers and Boden seem to have made quite a good job of it).

The witches (Isis, Astarte, Demeter) although I heard it sung pretty well by Roy Bailey last weekend.

We used to get Tom Dooley and Michael Row the Boat ashore a lot in the UK too, in the days of the Kingston Trio.

The Anchor Middle Bar session in Sidmouth has a sign saying "NFD" which means no effing dirges. But what you can sing without being fined depends on whether it has a chorus, and the attitude with which it is sung.