This is the 4th of 6 articles on cooking and heating with wood. Today I’m talking about the different woods that are available to you and which you should choose for each burning need.
Wood fuel is rated by BTU — the British Thermal Unit is the amount of energy required to raise 1 pound of water 1 degree Fahrenheit. The term BTU describes the energy content of fuels — the higher the number, the better the fuel is for creating heat and for cooking with.
All wood that is in an ideal condition for using in a wood burning stove or wood cook stove is:
Dry and seasoned
Free or low cost
Makes use of windfalls, dead trees, dangerous trees or selectively harvested trees
Doesn’t endanger the operator
Is untreated with chemicals
Has a high BTU (more about BTUs below)
Do your best to have your winter wood stacked and stored by the end of August. It needs to dry before you start using it. Burning green wood is frustrating. It doesn’t give off as much heat because the energy in the wood that you need to heat is being used to evaporate the water in the wood. Green wood will have sap and resins that can cause problems in your wood stove and flue. Green wood causes creosote build up in your chimney that can lead to dangerous chimney fires. Take the time to properly season your fire wood and bring home twice the wood that you think you need. This is the most important point — whatever wood you choose to burn.
Your heating needs depend on where you live and how well insulated your home is. Everyone’s needs are different. Wood that you would use to heat your house can be used for cooking with some craft and wisdom.
Although your wood cook-stove can be used to heat your home, when you want to cook you stoke the fire differently. You want your wood to catch fire quickly, and have a long burning time. Ideally we use a quick fire with lower BTU woods if we are getting the fire going in the morning or need to bring food to a boil or a simmer on the cook top. This heats the cooking surface fast. When you are baking or roasting in the oven — you want to use denser woods with a higher BTU, to burn more slowly and give an even heat, for slow, even cooking temperatures.
With the available woods that I have, I might start the fire with lodge pole pine logs , cedar kindling and a few alder logs. Once the fire is going I would feed it with pine, spruce, aspen or alder to keep it going on a cold day — these woods have a lower BTU but give off fast heat. Using these woods means that you have to add fuel more frequently, but they are the readily available woods and so we have more wood like this than the higher BTU woods — like birch and larch.
When I want to bake or roast in the cook stove oven, I need to add a longer burning wood with a higher BTU — larch or birch would give me the most heat for the longest burning. Those who live on the East coast have the benefit of eastern hardwoods — most of which, have higher BTUs than the available Western woods.
In Spring, when you wake up to a cold house but you know that the sun will come in the windows and heat the house by noon, you want to light a quick, fast fire that will take the chill off the house and heat your coffee pot, fry a few eggs and then quit for the day — you want the lower BTU woods. Willow, aspen, spruce are ideal for a quick, hot fire to take off the chill and then go out so that you aren’t sweltering later in the day.
People often under estimate their firewood needs in the summer. A cord of wood — 128 cubic feet — looks like a lot of wood when the sun is shining and you have other tasks to do. But in February, when the snow is still 4 feet deep, and the wind chill is -28C in the sunshine — it can take all day to bring home enough green wood to heat your house for one day.
Bring in twice what you need while the sun is shining in July and August and the wood has a chance to dry. Then you can spend your February days spinning by the fire, instead of hauling wood and you’ll save money and maybe even prevent a costly chimney fire. Our rule of thumb is, if you think you burn 3 to 4 cords of year — bring home 8 cords. Then the next year, fill your wood storage back up to 8 cords. This way you’ll stay ahead of your needs for dry wood and should unforeseen circumstance prevent you from getting wood next summer — you will have dry wood to keep you going.
Here the dominate woods are soft woods like pine, cedar, spruce, fir, and larch and hardwoods like birch, alder, willow and aspen. Conventional wisdom says to burn hardwoods, but some soft woods give you more fuel value. Dominant woods differ as you move across the country and you should use the available woods in your area.
Commonly Available Western woods and their BTUs
|Western Larch (Tamarack)||22.3|
|Douglas Fir (Red Fir)||20.6|
|Ponderosa Pine (Yellow Pine)||17.1|
|Grand Fir (White Fir)||16.7|
If you want to explore this topic further there is a useful pdf download from the Coleville National Forest, focused on heating with wood. This free pamphlet also offers a comparison of other fuels with wood heating and allows you to compare the relative costs of each choice for home heating based on BTUs. It tells me that if my alternate home heating is electric baseboard heaters and I am paying 10 cents per kwh then if a cord of firewood cost less than $300, I’m ahead. Last winter a truck load of larch (3/4 cord) was $85 in my region.
The Woodburner’s Companion: Practical Ways of Heating with Wood
This is the 4th in a 6 part series on cooking with wood.
Part 1, “12 Practical Reasons Why Cooking with Wood Makes Sense”
Part 2 , “Wood Heaters vs. Wood Cook-Stoves: How to Choose”
Part 3, “Wanted: The perfect wood cook-stove”
Part 4, “Burning Desire: Wood fuels for cooking and heating”
Part 5, “Maintenance tips for your wood cook-stove”
Part 6, “Objection! Heating and Cooking with Wood is objectionable”
Did I miss anything? Do you have a wood heating experience to share with our readers? Leave a comment.
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