If you are new to burning firewood, or even if you have been doing it for years, there are some important things to consider. What I am talking about is buying firewood, how to chose a firewood dealer, types of firewood and how to look after wood. I am not talking about harvesting wood from your woodlot, choosing a wood stove or burning wood safely.
Different species have different characteristics, but they all one thing in common, when wood has had a chance to dry and season the moisture content goes from an average of 60 percent down to 20 percent, which increases the heating value by 20 percent. Burning wet wood is inefficient as it does not give off so much heat and can create more creosote. BTU, British Thermal Units, measures heating value - the heat required to raise the temperature of one pound of water one degree Fahrenheit.
You should buy wood by the bush cord or a face cord. A bush cord is 8’ long, 4’ high and 4’ wide. A face cord is 8’ long, 4’ high and 16” deep. Logs are cut to 16 ‘ lengths, so a bush cord has three times as much wood as a face cord. A cord is the legal unit for the sale of wood. The price of firewood varies a great deal, not least depending in whether it is cut, split and stacked. One can buy wood by the truckload and cut it and split it oneself.
Hardwoods, i.e. deciduous trees that lose the leaves in winter, have a higher BTU or heat value, than softwood species i.e. conifers like pine and spruce that keep their needles. However, some hardwood species have much high BTU than others. When you are buying firewood, you need to know what you are buying. A cord of basswood and poplar will give you much less heat than cord of oak and ironwood. One should ask the dealer about this and check oneself. The photographs below are there to help with identification of the different species.
Ironwood has a high BTU of 31,000,000 per dry cord. One finds ironwood in maple woods that have been grazed by cattle for a long time. The wood is very hard and great for burning.
Oak is a good wood to burn with a BTU of 30,600,000 per dry cord however it takes longer to season than some other species.
Hickory is a good wood to burn with a BTU of 29,200,000 per dry bush cord and is used for smoking meats.
Beech has a BTU of 27,800,000 per dry bush cord and is easy to recognize with its smooth grey bark.
Ash is a good firewood and will become plentful when the Emerald ash borer comes into this area and trees die. Ash has a BTU of 25,000,000 per dry cord and seasons more quickly than some species.
Elm burns well with a BTU of 24,500,000 per dry cord but is difficult to split. Dutch elm disease is still common in this area and there are many dead elms.
Black cherry has a rich colour and distinctive bark. The BTU value is 23,500,00 per bush cord.
White birch is easy to recognise with its papery bark. Its BTU value per bush cord is 23,400,000. Yellow birch has a higher BTU 26,200,000 per bush cord, but has an equally distinctive yellowy bronze bark.
Silver maple has a BTU per bush cord of 21,700,000 and is a medium quality firewood.
Aspen does not have a high BTU per bush cord at only 18,200,000. It can usefully be burned with other hardwood when a hot burn is not needed.
Basswod has a BTU per dry bush cord value of 17,000,000. The wood is soft and easy to split.
Pine and other soft woods do not have high BTU per bush cord values at around 17,000,000, but if they are dried well one can use them for firewood, but they will burn more quickly than hard woods
Make sure any wood you burn is well seasoned. Look at the end of the log and see if there are checks or cracks and the wood has darkened. Firewood should be cut in the winter before the sap rises and be left to season in the sun and wind through the summer. Store firewood under shelter to protect it from the rain.
Buy firewood harvested locally, and do not buy wood trucked in from elsewhere. There are a number of forest pests, such as the emerald ash borer that affects ash trees that can travel on firewood from an affected area to an unaffected area.
Fuelwood in the 21st Century is a useful article put out by the Ontario Woodlot Association.