Which instrument is commonly used to measure tree height?

The clinometer is commonly used to measure tree height because it allows users to determine the angle of elevation to the top of the tree and then calculate the height based on that angle and the distance from the tree. This device leverages the principles of trigonometry, where the angle and horizontal distance can provide an accurate height measurement when combined.

While a laser rangefinder can also be used for measuring height by directly calculating the distance to the top of the tree, the clinometer is specifically designed for measuring the vertical angle, making it a traditional and widely accepted tool in forestry for this purpose.

GPS devices are primarily used for locating positions on a map and do not measure height directly, and measuring tapes are typically used for measuring horizontal dimensions rather than vertical heights, making them less practical for tree height measurement.