

Add the height of your eyes to the calculated height of the tree.Where opposite is the height of the tree and adjacent is the distance between you and the tree. Use the Tangent rule to calculate height of the tree (above eye level).

Do this with a measuring tape or wheel for a more accurate result. Now that you have the angle, measure the distance between the tree and where you were standing in step one.If you don’t have a clinometer you can just mark the angle on a peice of card and measure using a protractor. Release the lever to trap the indicator and then read off the indicated angle. Put the clinometer to your eye and line it up with the top of the tree while holding the lever (lets the indicator swing freely). You need to be far enough back that you can easily see the top of tree. Measure the angle between the top of the tree and the ground from your eye.Measuring the height of a tree using trigonometry. For this method you will need clinometer and a way to measure your distance from the base of the tree. When you use an angle other than 45° (when you are forced to stand closer or further away) the math is a little more involved. With an angle of 45°, the math is easy and height equals distance. This is the ‘full version’ of the 45° triangle method above. In that case you would need to use the ‘full version’ of this technique, the trigonometry method. Remember you calculated the tree height from your eye level and so you need to add your height for total tree height.Ī limitation is when the tree has a spreading canopy, you might be unable to see the top with a 45 degree angle. Add the measured distance/height to your eye height.The distance is equal to the height of the tree from the height of your eye (see diagram above for clarification). Measure the distance from where you stand in step 3 to the base of the tree.Move backwards/forwards until your eye lines up with the top of the tree and the two shorter sides run parallel with the ground and tree trunk.Hold the triangle up to your eye and look along the longest side at the top of the tree.Fold the paper/card square in half to make a 45° right angle triangle.Measuring the height of a tree using a 45 degree angle.
