Question

A T.S. of a trunk of a tree shows concentric rings which are known as growth rings. How are these rings formed?

Answer 1

• In the spring season, cambium is very active and produce a large number of xylary elements having vessels with wider cavities and are called spring or early wood and is lighter in color.
  
• In winter season the activity of cambium reduces and it forms xylary elements having vessels with narrow cavities and is considered as autumn or latewood and is dark in color.

These both rings appeared as alternate concentric rings and constitute an annual ring which is used to estimate the age of a tree.