When they get to the master level of trading, fishermen will trade an emerald for a boat. However, it seems they will take only one type of wood boat. The one I'm trading with wants a spruce boat and it would be nicer if I could sell him oak boats from all the mineshaft delving I do. I'd replace him except then I'd have to raise a new one to master class without knowing in advance what wood he would want.
Spruce seems to be one of the quickest trees to get lots of wood from fast...that would be perfect! The 4x4 spruce grow fast, have no branches, and provide tons of wood. I'd say you're lucky!
Oh, I don't have any trouble getting Spruce wood. In fact it and Birch are my major lumbering trees for charcoal and such. The problem is, I have a ton of Oak boards from mineshaft delving and would like to unload some of it.