Why this matters now
Forest types, their rainfall thresholds and characteristic species/regions are a frequent prelims theme — and the basis for biodiversity and conservation questions.
Factors controlling vegetation
Vegetation is governed by temperature, rainfall, soil, relief (altitude) and drainage. Rainfall is the key control in the plains; altitude dominates in the mountains. (Note: “natural vegetation” in much of India is actually modified by human activity.)
Major forest types
- Tropical evergreen (rainfall >200 cm) — Western Ghats, NE, A&N Islands; dense, multi-layered (rosewood, mahogany);
- Tropical deciduous (monsoon forests) — the most widespread (100–200 cm); moist (teak, sal) and dry types;
- Thorn & scrub (<50 cm) — NW arid regions (acacia, cacti);
- Montane forests — altitudinal belts (oak, deodar, alpine meadows);
- Mangrove (tidal/littoral) forests — deltas/coasts (the Sundarbans, with sundari trees).
Distribution and conservation
Forests are unevenly distributed — dense cover in the NE, Western Ghats and central India. They are vital for biodiversity, livelihoods, climate and water security, and protected through forest laws, reserves and afforestation (linking to the environment syllabus).
UPSC angle
Match forest type to rainfall and region — evergreen (>200cm, W.Ghats/NE), deciduous (100–200cm, most widespread, teak/sal), thorn (<50cm), montane (altitude), mangrove (Sundarbans/sundari).
Frequently asked questions
What controls natural vegetation in India?
Temperature, rainfall, soil, relief (altitude) and drainage — with rainfall the key control in the plains.
Which is the most widespread forest type in India?
Tropical deciduous (monsoon) forests, found in areas with 100–200 cm of rainfall.
Where are tropical evergreen forests found?
In high-rainfall (>200 cm) regions like the Western Ghats, the North-East and the Andaman & Nicobar Islands.
What are mangrove forests?
Salt-tolerant tidal forests of deltas and coasts, such as the Sundarbans with its sundari trees.