Students and forestry specialists, tree physiology, and forest ecology sectors often have to measure tree growth. To do this, they usually use a dendrometer, or special measuring band. Also known as D-tape, diameter tape is a type of dendrometer used to measure the diameter of the shaft.

Diameter measuring tapes are generally made up of fabric or metal, and expressed in units of 3.14, or an estimate of the unit pi, inches or centimeters. They are generally used to measure the diameter of a chest tree. This is considered four and a half feet (137.16 centimeters) above ground. Measuring the diameter at chest prevents the meter from calculating the width of the base of the tree, which would reflect an inaccurate diameter of the overall tree.

Although tape diameter actually measures the circumference of a tree, it easily converts diameter. This is because the circumference and diameter are linked by fig. However, the diameter tape does not provide accurate measurements completely, as it is assumed that internal sections of the shaft are in perfect circles. The values obtained are therefore considered an approximation.

To measure a tree, the tree root must first be prepared before using the diameter tape. The surface must be free from knots, branches, or other obstacles. The circumference in which the tape will be used should be sanded with a file or sandpaper. It should be used during this process to avoid damaging the tree.

A person must make sure that the diameter tape is at the breast level. The tape must be perfectly level, with no creases or twists in it to ensure the most accurate reading. The diameter side should be high, facing the meter. When the number zero aligns with the end of the tape, the diameter can read the tape.

After measurement, the circumference can then be converted to a diameter. This is done by dividing the circumference by approximating the pi of the unit, 3.14. Mathematicians will recognize the use of the equation for circumference solving by diameter.

By evaluating the diameter of a tree in combination with its height it is important to note the wood volume of the tree. During sale of the tree for cellulose, timber, or for other purposes, its volume is necessary for correct evaluation and use. To estimate the volume of wood in standing trees, tree volume tables are used. Displaying average diameters and heights, these tables list diameters along a matrix to portray a quick display of the volume of wood