UPSC Practice recommends Under the world cup tree, oh where will you and I next be?.
The age of trees can be measured by looking at tree rings, concentric circles visible upon cutting cross-sections through a trunk. Each ring marks a complete cycle of seasons forming a year in a tree’s life, the closest ring to the bark being the youngest and the innermost at the centre, the oldest. The larger the number of rings, the older a tree.
Courtesy: Opinion-Economic Times