The study of form is beset with difficulties because it can not be fixed by one or two measurement. This is due to the fact that the form varies not only from tree to tree but also in the different parts of the same tree. Variation in bark thickness not only from stand to stand and tree to tree but also in the different parts of the same tree adds another dimensions to the problem. However, the form of a tree can be studied in one of the following ways:

1. By comparison of standard form ratios (form factor and form quotient)
2. By classification of form on the basis of form ratios and
3. By compilation of taper tables