Wikipedia distinguishes them, and that's in line with my understanding, although I don't know that my understanding wasn't derived at some point from Wikipedia or a descendent source.

As Wikipedia (and, apparently, G. E. Moore) would have us believe, the "naturalistic fallacy" is believing that you can reduce good/bad to natural states, and seems more closely related to Hume's "is-ought problem" than to the "appeal to nature". I actually think this comes down to disagreement about what is meant by "good/bad" more than substance, though.

Clearly, some do use "naturalistic fallacy" to mean "appeal to nature", and I'm not certain the original use of the term is worth preserving as distinct from Hume, but I'd encourage "appeal to nature" for clarity since that seems to have no ambiguity.