Since a tree is shaped like a cylinder, its volume may be determined by measuring its diameter and height. Diameter of standing trees is measured by time-honored custom, at 4-1/2 feet above ground on the uphill side of the tree. This is abbreviated as DBH (diameter breast height.) The way to determine diameter will be explained in detail later. Height of a standing tree might be measured as total (the entire height from ground line to the top) or merchantable. Merchantable height varies, depending on the product which might be cut. If a tree might make a pole or piling, the height used will be measured in 5 foot increments. The top diameter is fixed by certain specifications. If a tree is to be cut into logs, its height usually will be measured in 16 foot logs to the nearest full log (change made 11-06).

To measure diameter, you may use a caliper, diameter tape, or tree scale stick. Since the tree scale stick is to be used in the contest, the method of using it will be explained.

The drawing below shows how the tree scale stick is used to find tree diameter. Use the flat side of the stick, which reads, "Diameter of Tree (in inches)." The instrument on this side of the tree scale stick is called a Biltmore Stick. Hold the stick level at 25 inches from the eye, against the tree, at a height of 4-1/2 feet above ground. Practice is needed to find both the 4-1/2 foot point in relation to your height, and the 25-inch distance to your eye. When the stick is placed against a tree, close one eye, sight at the left or zero end. This and the tree bark should be in the same line. Now, DO NOT MOVE YOUR HEAD. Just move your eye across the stick to the right hand edge of the tree. Read the tree diameter to the nearest even inch (10, 12, 14 inches, etc.). Hold the stick perpendicular to the tree.

To measure the merchantable height of a tree, pace out 66 feet from the base of the tree, to a point where the entire tree can be seen. It is a good idea to stay on the same contour as the tree rather than up or down hill from it. Hold the tree scale stick so that the edge of the stick that reads "Number of 16 foot logs" faces you. The instrument on this edge of the tree scale stick is called a Merritt Hypsometer. The zero end should point toward the ground. Plumb the stick, at 25 inches from the eye. Sight the zero end to appear to rest at stump height. DO NOT MOVE YOUR HEAD OR THE STICK. Look up the stick to a point where the top of the last merchantable cut would be made in the tree. (Eight inch diameter or at the first major fork or other major defect.) Read the merchantable height to the nearest full half-log. If the merchantable height is slightly more than 2 1/2 logs you can record it as 2 1/2 logs. But, if the merchantable height is slightly less than 2 1/2 logs you must record it as 2 logs.

Practice on pacing is needed to find the 66-foot distance from the tree. The 25-inch distance from your eye to the stick is still the same as in measuring tree diameter.