As a general rule, we let the salvia threads stay, actually. Unless discussion of other illegal drugs comes into play, that is. Or unless other they generate other trouble of some kind. Salvia's still legal in most places (that's apparently in the process of changing, however), and, unless I'm mistaken, there was a time when salvia advertisements were part of this board. Anyway, it's the discussions of other illegal substances that are more of what the owners had in mind when making that particular cannabis-only rule.