With all the fish fanatics, I'm suprised no one mentioned alder wood for smoking.  It has a much lighter flavor than hickory or mesquite and there's tons of if in north woods.  It's especially good with salmon and probably likewise lake trout.  When I cook steaks up in canoe country, I will seek this out to add to my cooking fire as it adds great flavor to beef as well.  If you get into smoking fish for jerky it is usually best to brine it first for a bit (time depending on thickness of cut) as the salt helps draw the moisture out.  I usually use a quarter cup salt per quart of water.  Lots of great recipes on line with a simple search.  I add lib a lot and prefer dry rubs of various kinds, but my go to is one part McCormick's fajita seasing and one part Zatarain's Creole seasoning.  Good eatin'!

pd