Sub-Section 127, Wood Measurement
Internal Revenue Manual
Specialized Industry Guidelines - Timber
Sub-Section 127, Wood Measurement
Last amended: 6-26-1978
Wood Measurement
(1) The subject of weights and measures is important in any business that handles tangible products. The timber business is certainly no exception. The estimated quantity of timber standing on the stump has traditionally been expressed in board feet, meaning the number of board feet log scale that should be contained in the logs recovered from the timber after it is cut. The board foot is still the prevailing unit of measure for larger or old growth timber, such as that predominating in the west.
(2) In smaller second growth or new growth timber, especially in softwood stands, timber estimates are often expressed in total cords or cunits. A cord of wood is by definition a stack of wood measuring 4' x 4' x 8'. A cord of wood, therefore, occupies 128 cu. ft. of space. Obviously, a cord of wood will contain a lot of air space and tree bark. The amount of solid wood in a cord might easily vary from 70 to 90 cu. ft.--depending on variables such as diameter, straightness, and taper of the sticks.
(3) A cunit is an absolute quantity of 100 cu. ft. of solid wood. Any conversion of cords to cunits is at best only an estimate.
(4) It is much easier to determine the weight of a truckload of logs or cordwood than it is to measure the number of cords or board feet log scale. For this reason, weight scaling is becoming more and more popular. Again, when tons of logs are converted to cords or board feet log scale, the result is only an estimate. The conversion rate will depend on many variables such as species of wood, moisture content, size and taper of the logs, and other factors.