Step 1: Take ordinary scale.
Step 2: Measure ground stem up to the growing point of the plant.
Step 3: Use Indian ink and mark at regular intervals to measure the length of root, stem, and girth of the trunk.
Observation: At regular intervals measure the increase in length and girth of the trunk and it can be observed that the length of the root, stem and girth of the trunk increased with the increase in the period of growth.