It is my understanding the allure of wool applique is it is all raw edge, you don't have to turn under because it doesn't fray because the wool has been felted (washed and dryed so it shrunk up good and tight). At least that is my understanding. You just buttonhole stitch around. But do you have to fuse it? I haven't inspected it closely when seeing it at booths or in shops. It is very appealing though.
I want to master needleturn first though.