UPSC Prelims 2011 question on Girdling Tree Bark

Analysis

When bark is removed in a circular ring around a tree, the phloem is cut. This stops the downward movement of food from leaves to roots.

1. Roots are starved of energy — Correct

The bark contains phloem, which transports sugars made by photosynthesis from leaves to roots.

When the bark is removed all around the tree, this food supply is cut off. The roots starve, die, and the whole tree gradually dries up.

2. Roots cannot absorb water immediately — Incorrect

Water is transported mainly through xylem, which lies deeper inside the stem.

Removing bark does not immediately stop water movement, but roots eventually die due to lack of food.

3. The tree cannot carry out photosynthesis — Incorrect

Leaves can still perform photosynthesis for some time.

The problem is that the food produced cannot reach the roots.

4. Infection kills the tree immediately — Incorrect

Infection may occur later, but it is not the main reason for gradual death.

The primary cause is interruption of phloem transport and starvation of roots.