Question

A cut trunk shows $26$ concentric rings of spring wood and autumn wood in alternate rows. The age of trunk would be.

• A. $13$ years
• B. $26$ years
• C. $52$ years
• D. $104$ years

Answer 1

The correct option is A $13$ years

In dicotyledonous stems, during intra stellar secondary growth, a ring of cambium called vascular cambium is formed. In the plants growing temperate regions, the activity of vascular cambium is influenced by the existence of maximum seasonal variations. In the spring or early summer, due to the existence of favourable conditions, a large amount of secondary xylem is formed. it is called Springwood or early wood. In the autumn season, due to the presence of unfavourable conditions, less amount of wood is formed. it is called autumn wood or latewood. Every ring of spring wood and autumn wood together form into an annual ring. In the 26 rings, 13 rings constitute spring wood and 13 rings constitute autumn wood. So total 13 annual rings are present.

So, the correct option is '13 years'.