Firewood

Gathering Firewood

When using a fireplace or wood stove for heat, you can, of course, cut and gather your own firewood. That not only requires a healthy amount of time, however, but also requires an initial investment of equipment like axes and saws and splitters. It also demands a working knowledge of cutting wood. You may need to acquire permits from the U.S. Forest Service or State agencies such as the California Department of Forestry and Fire Protection.

You Can Also Purchase Firewood

Although there are a variety of measuring units, firewood is normally sold by the cord, or a fraction of a cord. The dimensions of a "standard cord" is a stack of wood piled 8 feet long, 4 feet wide and 4 feet high. You won't get a full 128 cubic feet of firewood with a standard cord because of the airspace between the pieces of the wood; the amount of wood in such a stack will depend upon the size and straightness of the pieces, how they are split and how the wood is stacked. Because of this, the total cubic feet in a cord can vary from 70 to 90 or more cubic feet.

The cost of firewood varies according to the number of services a wood dealer furnishes -- tasks such as splitting, delivering and stacking. The cost also varies in different geographical areas.

Orders for the purchase and delivery of firewood should be placed well in advance of the heating season. Wood purchased during the peak periods is in more demand and becomes more expensive. You will also want to purchase early to give the wood time to season.

Seasoned Wood

Seasoning takes place when the moisture content in wood reaches equilibrium with the moisture in the surrounding air.

When wood is stacked outdoors with good air circulation in a spot that's dry, sunny and open for about six months it will be dry enough to support efficient combustion. Seasoned wood has a higher heating value than green wood. In general, because of its moisture content, a cord of green wood will weigh 70 to 100 percent more than seasoned wood.

The time of year and the size of the wood pieces influences the amount of time that wood takes to season. You can help the process by properly stacking and storing your pile of firewood. The best way is to store it outside, under cover and close to the house for easy access. It should be stacked on a supporting base -- such as cement blocks, pallets or wooden planks. This prevents the wood from drawing moisture from the ground, allows air to circulate around it, reduces insect infestation and cuts down on the amount of dirt in accumulates. End braces or stakes can be used to keep the woodpile from collapsing; they can be built to measure accurately a standard cord.

The Best Woods For Burning

In either a wood stove or fireplace, the easiest and best fire is built by using a mixture of both softwoods -- from trees such as pines and firs -- and hardwoods -- oak, eucalyptus, cedar and so on.

Softwoods start burning easily, and the hardwoods provide for long burning and good "coaling" qualities. A bed of ashes underneath the grate produces steady heat and aids in igniting new fuel as it is added. The fire will continue burning if small amounts of wood are added at regular intervals. In fact, more efficient combustion results from burning small loads of wood with sufficient air than from burning large loads with minimal air.

Below is the average energy content of various species of wood.

Wood Heating and Weight Values
Species Million Btu/Cord* Cord Weight
(pounds) **
DRY
Cord Weight
(pounds) **
GREEN

Alder, Red
18.4 - 19.5 2000 - 2600 3200 - 4100
Ash 24.5 - 26.0 2680 - 3450 4630 - 5460
Aspen 17.0 - 18.0 1860 - 2400 3020 - 3880
Beech 28.6 - 30.4 3100 - 4000 4890 - 6290
Birch 25.9 - 27.5 2840 - 3650 4630 - 5960
Cedar, Incense 17.8 - 20.1 1800 - 2350 3020 - 3880
Cedar, Port Orford 20.7 - 23.4 2100 - 2700 3400 - 4370
Cherry 22.3 - 23.7 2450 - 3150 4100 - 5275
Chinquapin 23.2 - 24.7 2580 - 3450 3670 - 4720
Cottonwood 15.8 - 16.8 1730 - 2225 2700 - 3475
Dogwood 28.6 - 30.4 3130 - 4025 5070 - 6520
Douglas-Fir 23.5 - 26.5 2400 - 3075 3930 - 5050
Elm 22.3 - 23.7 2450 - 3150 4070 - 5170
Eucalyptus 32.5 - 34.5 3550 - 4560 6470 - 7320
Fir, Grand 17.8 - 20.1 1800 - 2330 3020 - 3880
Fir, Red 18.3 - 20.6 1860 - 2400 3140 - 4040
Fir, White 18.8 - 21.1 1900 - 2450 3190 - 4100
Hemlock, Western 21.6 - 24.4 2200 - 2830 4460 - 5730
Juniper, Western 23.4 - 26.4 2400 - 3050 4225 - 5410
Laurel, California 24.6 - 26.1 2690 - 3450 4460 - 5730
Locust, Black 29.5 - 31.4 3230 - 4150 6030 - 7750
Madrone 29.1 - 30.9 3180 - 4086 5070 - 6520
Magnolia 22.3 - 23.7 2440 - 3140 4020 - 5170
Maple, Big Leaf 21.4 - 22.7 2350 - 3000 3840 - 4940
Oak, Black 25.8 - 27.4 2821 - 3625 4450 - 5725
Oak, Live 34.4 - 36.6 3766 - 4840 6120 - 7870
Oak, White 26.4 - 28.0 2880 - 3710 4890 - 6290
Pine, Jeffery 19.3 - 21.7 1960 - 2520 3320 - 4270
Pine, Lodgepole 19.7 - 22.3 2000 - 2580 3320 - 4270
Pine, Ponderosa 19.3 - 21.7 1960 - 2520 3370 - 4270
Pine, Sugar 17.3 - 19.6 1960 - 2270 2970 - 3820
Redwood, Coast 17.8 - 20.1 1810 - 2330 3140 - 4040
Spruce, Sitka 19.3 - 21.7 1960 - 2520 3190 - 4100
Sweetgum (Liquidambar) 20.6 - 21.9 2255 - 2900 4545 - 5840
Sycamore 21.9 - 23.3 2390 - 3080 4020 - 5170
Tanoak 25.9 - 27.5 2845 - 3650 4770 - 6070
Walnut, Black 24.5 - 26.0 2680 - 3450 4450 - 5725
Western Red Cedar 15.4 - 17.4 1570 - 2000 2700 - 3475
Willow, Black 17.5 - 18.6 1910 - 2450 3140 - 4040

* British thermal unit (Btu) values based on specific gravity of 80 cubic feet per cord. 8000 to 8500 Btu per pound for non resinous woods. 8600 to 9700 Btu per pound for resinous woods.

** Weights:
  • Lower value of range assumes 70 cubic feet of wood per cord.
  • Higher value of range assumes 90 cubic feet of wood per cord.
  • Dry weight at 12 percent moisture content.
  • Green weight at 40 to 60 percent moisture content.

All moisture contents based on "wet" wood basis.