When the bark of a tree is removed in a circular fashion all around near its base, it gradually dries up and dies because

When the bark of a tree is removed in a circular fashion (girdling), the phloem tissue, which is located in the inner layer of the bark, is severed [4]. The phloem is responsible for the translocation of photoassimilates, such as sucrose and other sugars, from the leaves to the rest of the plant, including the roots [5]. While the xylem remains intact and continues to transport water and minerals upward from the soil [2], the downward flow of energy-rich carbohydrates is interrupted [4]. Consequently, the roots are deprived of the necessary energy stores required for their growth and metabolic maintenance. Over time, the roots are gradually depleted of their carbohydrate reserves and suffer from starvation. Since the roots can no longer function or support the tree's structural and nutritional needs, the tree eventually dries up and dies.

Sources

1. [4] Science-Class VII . NCERT(Revised ed 2025) > Chapter 10: Life Processes in Plants > In a Nutshell > p. 150
2. [1] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > Transport of food and other substances > p. 96
3. [3] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 13: Plant Diversity of India > Bark; > p. 204
4. [5] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/girdling
5. [2] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > 5.4.2 Transportation in Plants > p. 94