Mostly it seems just cleaning out the ash is the main thing that needs to be done on a regular basis. Yeah he said we can burn pine and even green wood if we want. It burns better with seasoned hardwood but it can handle just about whatever timber you throw at it. At least that is what my installer told me.
Ah yeah black locust would be superior but handling it is such a pain in the ass with all its thorns.
That is awesome that it can burn a variety of wood types!
Once black locust is no longer a juvenile tree it loses its thorns and some strains of it have very few thorns to start with.
If you think those are thorny check out the Honey locust tree that just gets thornier with age!