By the way, as with other aspects of ballad transmission - their movement is a little more complex than just the Northern Ireland/ Scotland route.
Probably the most popular ballads sung around in the mid West here by source singers is The Suffolk Miracle and Lord Lovell, which, as far as I know, have not turned up in the North.
Hugh Shields once wrote a fascinating article on the transmission of Lord Gregory, also not found in the North (as far as I know).
Just before we came to live here 13 years ago we heard Peter Cook give a talk in Aberdeen on the influence in the other direction - from Ireland to Aberdeenshire - fascinating.
Jim Carroll