There are many who use wood they find here and there. It does not have to be anything special if one is ready to deal with what he may find. Wood from the yard or really any place can be cleaned up to remove oils or pesticides they might have on them. Nothing wrong with soft wood except we have to accept that it may not last as long as a hardwood might. Some of the softwoods will have more sap and maybe a bit more trouble to deal with over time but that doesn't mean we have to rule them out if we are ready to do the work that may follow.
Like everything else in the tank, we have to make a personal decision as to what is worth the trouble and what is not.
Like everything else in the tank, we have to make a personal decision as to what is worth the trouble and what is not.