Tools of the Trade Forestry Quiz

What is this clinometer used for?
©Photo courtesy of Ben Meadows Company, Janesville, WI

This tool is used by foresters to:

a) measure the height of a tree
b) measure the rate of sap flow
c) tell what direction they are walking
d) measure the windspeed

The correct answer is “a.” The clinometer is used to measure how tall a tree is. The round dial in the center of the clinometer floats, similar to the arrow on a compass. The forester stands a known distance from the tree to be measured. There is a peep hole on one end of the clinometer, where you can read the numbers on the floating scale.

The forester points the clinometer at the top of the tree.

The forester points the clinometer at the top of the tree, then reads the number on the scale. This number is added to the number read when aiming at the base of the tree to determine the total height of the tree. This tool uses the math concepts involving right triangles that you learn about in trigonometry. (So, study your math!) Foresters can tell how well a tree is growing if they can measure the tree’s height compared to its age. They also use the height measurement to figure out how many logs (and later, boards) they will get when the tree is cut down.

On to the next question...