The key to understanding the BTU content in wood is all about understanding density.
Remember the old trick question, “Which weighs more: one ton of bricks or one ton of feathers”? The answer, of course, is that they weigh the same, one ton is one ton. But it would take a lot more feathers to create one ton of weight than it would bricks because of the difference in density between the two objects.
The same is true for wood. Generally speaking, one pound of wood is going to produce the same BTU content regardless of what type of firewood it is. But the way that it will burn will be vastly different depending on the type of wood because of density.
A type of wood that is not very dense, such as pine, will produce a lot of BTU content very quickly, but die out after a relatively short amount of time. Anybody that has sat around a campfire has probably tossed a paper plate into the fire at the end of a fireside meal. The plate, which is far less dense than wood, usually creates a big flame, but is gone to ash after a few seconds. The same principle, albeit on a slightly lesser scale, is true for softer woods.
That makes those types of less dense wood good for fireplaces or campfires, where they will give off a lot of heat, but they are not very good woods for smoking. Even if pine wood smoke didn’t give off an unpleasant taste, it would be remarkably difficult to smoke with because the wood burns hot and would need to be replenished constantly.
The best woods for smoking are extremely dense woods, such as oak or hickory. While they give off the same total BTU content as less dense woods, they will do so at a lower temperature over a longer period of time. And as any barbecue enthusiast will tell you, the biggest key in smoking great barbecue is to go low and slow. The lower temperature over a longer time allows the meat being smoked to absorb more smoke and all of the delicious flavors that come along with it, without the meat drying out by being overexposed to the heat.
So while all woods may have the same BTU content by weight, it’s a matter of understanding how you want your fire to burn and how to use those BTUs to your greatest advantage. Soft woods will produce a lot of heat, but burn out very quickly, while dense woods will burn at a lower temperature over a longer period of time.
The firewood experts at Wisconsin Firewood know the best wood for your situation. They can help you find the best wood whether you are barbecuing, smoking, or need wood for a fireplace. Give them a call at 414-769-9663 and they will guide you in the right direction.