Plane Trees In The Circus [Part Two]

Here is a simple way to estimate the height of a tall tree:
Break a stick so that it is the same length as your arm. Hold your arm out straight with the stick pointing straight up (90-degree angle to your outstretched arm). Walk backwards until you see the tip of the stick line up with the top of the tree. Your feet are now at approximately the same distance from the tree as it is high (provided the tree is significantly taller than you are, and the ground is relatively level).