Estimating the size of a tree can be tricky. Full assessments will usually require a specialist using sophisticated equipment. However, for a preliminary assessment, there are a few techniques you can use to estimate the size reasonably. This page sets out some methods for estimating the size.
Using a reference
Object | Typical height |
A post box (pillar box) | 1.5m |
Average human male | 1.62m |
Average human female | 1.75m |
A typical house in the UK | 6 - 7.5 metres |
Pencil method for calculating the size
You will need a pencil
A friend
Step One: Hold the pencil in front of you so that the top of the pencil aligns with the top of the tree. Hold the pencil between your thumb and index finger.
Step two
Keeping the pencil in the same position, move your thumb down so it aligns with where the tree touches the ground.
Step three
Keeping your thumb in position, move the tip of the pencil so it aligns with the ground, so the tree and pencil together form a triangle.
Step four
Ask your friend to stand where the tip of the pencil aligns.
Step Five
Ask your friend to take big steps towards the tree - record the number of steps. Multiply the number of steps by your friend’s average step length (about 0.75 m per step for most adults). The result is the estimated height of the tree!
