well, let's see........tonight in the OWB was a mixture of popple, red oak, soft maple, elm, and yellow birch. Also on hand: white ash, balsam (was free and easy access), hard maple, ironwood, hemlock, cherry, pine, basswood, and bitternut hickory; might be forgetting one or two more. Not too fussy about segregating species, the temperature and time of year dictate what I normally grab and throw in the stove: like most wood burners, the best hardwoods are used during the coldest winter days/nights; summertime when we're only heating hot water, it's normally less than prime stuff: what's dead and lying on the ground.....somewhere between punky and primo red oak.
If it's easy access and doesn't fall in the marketable timber category, it'll get whacked for firewood, eventually. Never met a Btu I didn't like.