I've been looking at that maple for 30 years which ran parallel and ten feet from my external stove pipe.A tree cutter friend finally took it down yesterday and now I see how a tree can interfere with your draft.My draft has increased and reloading down draft has been reduced greatly.The next step will be to use the double wall pipe for the blaze king and my troubles with smoke spillage should be totally solved.Well I'm off to split up the half cord of wood the tree yielded,take care.