The Wet Woodland Plant Survey
How to Calculate The Height of a Tree
h = height of survey observer (to eye level)

Above: Measuring the height of a mature tree.
Where a tree is too tall for its height to be measured directly, it can easily be
calculated using simple trigonometry. The survey recorder stands at a measured
distance from the base of the tree (baseline B). Using a handheld device called a
clinometer, he or she measures the angle in degrees between the horizontal, their eye and
the top of the tree (the angle bpt = angle A). Then, using tangent
tables (obtained from trigonometrical tables or from a calculator) and the equation Height
of Tree = h + B x tan(A), the
survey recorder can calculate the height of the tree and record it in a table. 
Back to Wet Woodland Survey Methods
