Just let him know that there's a whole nation called Canada that burns a LOT of conifers to heat their homes. Then there's those damp Washingtonians too...
Don't Forget us waterlogged Oregunians, I have heated with Douglas FIR(not FUR) Spruce and Hemlock(Tsuga), a Forced Air ELECTRIC Furnace is rough on the budget. Other than when we are out of town and can't keep the wood stove loaded, our furnace doesn't even get turned on.
At a previous house, I burned PLENTY of Lodgepole Pine in a Fireplace, never burned any of my houses down, I would LOVE to have access to more hardwoods, but if that was all I would burn, I wouldn't be having much more than occasional Ambiance Fires, forget about Serious Home Heating.
The Conifers don't give you as long of a burn time as most hardwoods, and for some of us that is just about all that is available to us in enough volume to heat with.
Anyone that is "AFRAID" to burn Pine, FIR, Spruce, Hemlock etc, Simply doesn't know any better.
Doug