[She hesitates a bit, considering how to answer. She isn't sure if she can convincingly pass herself off as a priestess but if he's scared of ghosts, she doesn't know how well he'd deal with the idea that she's a witch. So, she's going to be evasive...]

...Sort of. There's a lot of power in nature and if you combine it in the right way, it can be pretty effective. It won't chase off everything but it should help.