Wood – The Info You Need

Give more than just a passing thought to the wood you burn. Different types have different heat values. The heavier or more dense, the higher the heating value. Always burn dry, well-seasoned hardwood. If you buy green wood, it’s essential you season it before using. Green wood has too high moisture content for satisfactory results. Dry wood also helps decrease the amount of creosote build-up.

If you purchase your firewood, you’ll normally not have a choice of tree species. However, you should pay less for wood having a low heating value. Being a knowledgeable firewood buyer will help you get the most for your money.

Seasoned dense wood will burn long and steady, and one cord of such wood is equal to many gallons of fuel oil. A cord of hickory, for example, is equal to 177 gallons, while a cord of soft balsam fir is only equal to burning 96 gallons.

Wood is usually sold by the cord or rick. A standard cord stacked measures four feet wide, four feet high, and eight feet long. A rick is defined as eight feet long, four feet high, but only two feet wide (half a cord). A face cord is generally accepted to be four by eight by one or two feet, or as wide as the lengths of the wood cut.

If someone wants to sell you a “truck load,” it depends on the size of the truck bed. A pick-up truck with a basic four by eight foot bed, 19 inches deep, will only hold a third of a standard cord. If they claim they are selling “about” a cord of wood, and will deliver it in a pick-up, just explain you’ll pay after stacking it, but only for the actual volume you’re receiving.

There are long, long lists of dos and don’ts for wood burning stoves, but some of the more important ones are:

  • Use seasoned, dry hard wood.
  • Burn short, hot fires, rather than long, smoldering ones.
  • Install smoke/heat detectors, and have a good hand fire extinguisher nearby.
  • Empty ashes into a metal container with a tight-fitting lid. Keep the container off a combustible floor.
  • Don’t burn trash, papers, or small twigs.
  • Never use a flammable liquid of any kind to start a fire.
  • Never use chemical or starter logs.
  • Do not store dry wood near or under the stove.
  • Don’t leave the stove burning unattended overnight, or when children are in the house.
  • Never vent your stove into a flue already used to vent another heating system.
  • Do not leave the stove doors open except to fuel the fire.

On a pound-for-pound basis all wood contains just about the same amount of energy. However, on a volume basis there is a great difference in the heat given off by different woods. As a general rule, so-called “hardwoods” are more dense than “softwoods”. They burn longer and give off more heat than softwoods. The following table should help you in choosing which woods to burn:

Species Having High Heat Value
(1 cord = 21,000,000 – 24,000,000 BTU = 200-250 gal. of fuel oil or 250-300 cu. ft. of natural gas)
  • American Beech
  • Apple
  • Hickory
  • Ironwood
  • Red Oak
  • Sugar Maple
  • White Oak
  • Yellow Birch
Species Having Medium Heat Value
(1 cord = 17,000,000 – 20,000,000 BTU = 150-200 gal. of fuel oil or 200-250 cu. ft. of natural gas)
  • Big Leaf Maple
  • Eastern Larch
  • Elm
  • Red Maple
  • White Ash
  • White Birch
Species Having Low Heat Value
(1 cord = 12,000,000-17,000,000 BTU = 100-150 gal. of fuel oil or 200-250 cu. ft. of natural gas)
  • Aspen
  • Cottonwood
  • Hemlock
  • Red Alder
  • Redwood
  • Sitka Spruce
  • Western Red Cedar
  • White Pine