"Does that mean all the trad ballads are covers?" Good question and I suppose it depends on what any individual means by cover versions. The Concise Oxford defines 'cover version' in the following way

"a recording of a previously recorded song etc. made esp to take advantage of the original's success"

So I suppose theoretically at least according to that definition that could mean a new recording of a traditional song also. Pesonally though if I described what kind of material I did then I'd say a mixture of self penned, covers and traditional. And of course nowadays 'covering' something doesn't necessarily mean you are recording it. Many bands who play other people's songs live are called covers bands.