There difference can be described for instance this way. Herbalism is herbalism period however different paths use herbalism in different ways and methods each containing their own practices. For instance shamans use herbalism all the time and if I wanted to practice or study shamanic herbalism, I would hence forth call it shamanic herbalism, if I wanted to study herbal receipes and methods practiced by druids I would call it druid herbalism and so forth. Just as if I wanted to study herbal practices of satanism I would call it satanist herbalism. It just comes down to a matter of practice or belief really and how or what you call or name something.