The Woodland Education Centre - Woodland Restoration Project
The use of a clinometer to measure tree height.
A clinometer is a fairly simple instrument which is used to measure the angle of a slope. By using the principles of trigonometry, the height of tall objects can be calculated from the angles measured.
A clinometer can easily be made from a large protractor. A narrow piece of wood should be glued to the base of the protractor to act as a sighting line. A weighted plumb line is then fastened to the mid point of the base line of the protractor.
|To use the clinometer, hold the base (formed by the wooden sight) uppermost, so that the plumb line hangs down vertically (as shown above). Hold the clinometer out at arms length and sight along it, until your eye and your arm make a straight line to the top of the tree. Someone else should then read off the angle made by the plumb line on the protractor (Z).|
More information and a picture of a clinometer here
Random Sampling using a grid system