Introduction

You have probably walked through a forest on a picnic, or sat in a park in a city, or played under a mango, guava, or coconut tree in a village orchard. In each case, you are surrounded by plants. But here is the question the chapter opens with: how do you tell the difference between natural vegetation and planted vegetation? The same species of tree can appear in both places. A mango tree growing wild in a forest, with no one tending it, is part of natural vegetation. The same mango tree in your garden, watered and cared for by humans, is planted vegetation. The difference is not the species — it is the degree of human interference.

Natural vegetation, therefore, is defined as a plant community that has been left undisturbed over a long period of time. This long period of freedom from human interference is essential because it allows the individual species within the community to adjust themselves as fully as possible to the climate and soil conditions of the region. In other words, natural vegetation is nature's own arrangement — plants that have settled in an area on their own and adapted to their surroundings over time.

India is exceptionally rich in this regard. The country is a land of great variety of natural vegetation, and this variety is directly linked to the variety in its physical environment. Consider the contrasts:

• The Himalayan heights are marked by temperate vegetation, suited to the cooler climate of the mountains.
• The Western Ghats and the Andaman and Nicobar Islands support tropical rain forests, which thrive in conditions of heavy rainfall and warmth.
• The deltaic regions, where rivers meet the sea, have tropical forests and mangroves, adapted to wet, often saline, conditions.
• The desert and semi-desert areas of Rajasthan are known for cacti, a wide variety of bushes, and thorny vegetation, all of which survive with very little water.

The key point is that as climate and soil vary from one region to another, the vegetation of India changes accordingly. Vegetation is not random; it is a response to the environment.

Because of these variations, Indian forests can be classified into groups. The basis of this classification is certain common features shared by different regions — chiefly the predominant vegetation type and the climatic region. On this basis, Indian forests are divided into the groups that the chapter will go on to describe in the following sections.