Natural Vegetation and Forest Types of India
India is one of the few countries in the world that has almost every kind of natural vegetation, from the dense rainforests of the Western Ghats to the thorny bushes of the Thar desert and the alpine pastures of the Himalayas. Natural vegetation means the plant cover that grows on its own, without being planted or tended by people, and it is decided mainly by rainfall, temperature, relief and soil. Because the rainfall of India ranges from more than 11,000 millimetres in Meghalaya to less than 20 millimetres in parts of Rajasthan, the same country supports closed evergreen forests at one extreme and scattered thorny plants at the other. For the exams of Assam and the rest of India, the forest types, their rainfall ranges, their important trees and the records of forest cover are among the most reliable scoring areas, and this chapter brings all of them together.
How much of India is under forest
According to the latest State of Forest Report, the forest cover of India is about 21.71 per cent of the geographical area. If the tree cover outside the recorded forests is added, the forest and tree cover together comes to about 24.62 per cent. The National Forest Policy of 1988 laid down that at least one-third, or about 33 per cent, of the total land area of the country should be under forest or tree cover, and that in the hills the target should be even higher. India is still short of this goal, which is why afforestation and the protection of existing forests are repeated themes in government policy. The North-East is the richest forest region of the country: more than 65 per cent of the region is under recorded forest, even though the region has been losing green cover because of jhum cultivation, logging and encroachment. Among the eight states of the North-East, Assam has the lowest forest cover in relative terms, which is an important and often-asked fact.
The major forest types of India
Geographers group the natural vegetation of India into five broad families: the tropical evergreen forests, the tropical deciduous forests, the thorn and scrub forests, the montane forests of the mountains and the mangrove or littoral forests of the coasts and deltas. Rainfall is the single most useful clue: evergreen forests need more than 200 centimetres of rain, moist deciduous forests grow where the rainfall is about 100 to 200 centimetres, dry deciduous forests appear where it is about 50 to 100 centimetres, and thorn forests survive where the rainfall is below about 50 centimetres. The tropical deciduous forests, also called the monsoon forests, are the most widespread type and cover roughly 65 per cent of the total forest area of India. Around the Tropic of Cancer, where the rainfall is moderate and seasonal, the tropical dry deciduous and thorn forests dominate.
Tropical evergreen and deciduous forests
The tropical evergreen forests are tall, dense, multi-storeyed forests that stay green the whole year. They grow in the heavy-rainfall belts of the Western Ghats on their windward slopes, in the North-East and in the Andaman and Nicobar Islands. Rosewood, ebony and mahogany are among their most valuable trees. The tropical deciduous forests are less dense and shed their leaves for part of the year; teak, sal and bamboo are their best-known trees, and sal is valued as timber and for railway sleepers. The moist deciduous type, with its tall sal and the dense grass of the Terai, supports a great deal of wildlife, while the dry deciduous type shades into thorn forest as the rainfall falls. The largest rainforest of India is the Dehing-Patkai forest of Assam, and the Jeypore rainforest of Assam is famous for its Hollong trees. Tropical rainforests such as the Amazon are called the lungs of the Earth because they absorb carbon dioxide and release oxygen.
Thorn, mangrove and littoral forests
The thorn forests are found in the semi-arid regions of Rajasthan, Gujarat and Punjab, where the plants have thorns, small leaves and deep roots to reduce the loss of water; kikar, babul and khair are their main trees. The mangrove forests grow in the salty, tidal mud of the deltas and the coasts, and their trees have breathing roots. The Sundarbans, shared by India and Bangladesh, is the largest mangrove forest in the world, and its chief tree is the sundari. The littoral forests are the salt-tolerant woods of the seashore, closely related to the mangroves. Because mangroves weaken cyclones, hold the shoreline together and shelter fish, they are among the most valuable and the most threatened ecosystems of the country.
Montane forests of the Himalayas
In the mountains the vegetation changes with height as well as with rainfall, so the Himalayas show a complete ladder of forest types within a short distance. The foothills of the Himalayas carry tropical wet deciduous and semi-evergreen forests, and the Terai belt at their base is known for its tall grasses, swampy vegetation and sal forests. Higher up come the sub-tropical and then the temperate forests, where oak, chestnut, deodar, pine and the flowering rhododendron are common, and the Eastern Himalayan belt is especially rich in sub-tropical and temperate species. Still higher are the alpine pastures, used for grazing in summer, and then the permanent snow. The montane forests protect the watersheds of the great rivers and are the source of the timber, medicinal plants and fuel on which hill communities depend.
Forests of the North-East and sacred groves
The North-East is part of the Eastern Himalayan biodiversity hotspot and holds some of the wettest and most species-rich forests of India. Its people have a long tradition of protecting small patches of forest as sacred groves, which are community-protected woods of great cultural and religious importance; these groves, preserved by custom rather than by law, are living museums of local trees and animals. Mizoram is the leading bamboo-producing state of India, and bamboo is one of the most useful plants of the region. The shifting cultivation practised in the hills, called jhum cultivation in the North-East, is a major cause of the loss of forest in the region, together with commercial logging and encroachment. The Van Mahotsav, the tree-planting festival celebrated in the first week of July, was started to involve ordinary people in the task of increasing the green cover.
Quick revision
For quick revision, fix the numbers first: forest cover about 21.71 per cent, forest plus tree cover about 24.62 per cent, and the National Forest Policy target of one-third of the land. Remember that the tropical deciduous or monsoon forests are the largest type at about 65 per cent, that moist deciduous forests need about 100 to 200 centimetres of rain while dry deciduous forests need about 50 to 100 centimetres, and that the thorn forests of Rajasthan, Gujarat and Punjab carry kikar, babul and khair. Keep the records ready: the Sundarbans is the world's largest mangrove forest with the sundari tree, the Dehing-Patkai is the largest rainforest of India, the Jeypore forest is famous for Hollong, Mizoram leads in bamboo, the North-East has more than 65 per cent forest and Assam has the lowest forest cover among the eight North-Eastern states. Finally, the Van Mahotsav is the tree-planting festival of the first week of July and jhum cultivation is the great threat to the forests of the North-East.
How to prepare this topic
- Learn the four rainfall bands, because almost every forest question can be answered from them: evergreen above 200 centimetres, moist deciduous 100 to 200, dry deciduous 50 to 100 and thorn below 50.
- Make a table of forest type, region and chief trees - evergreen with rosewood, ebony and mahogany, deciduous with teak and sal, thorn with kikar, babul and khair and mangrove with sundari.
- Memorise the forest-cover figures and the National Forest Policy target of one-third, as these are favourite one-mark facts.
- Keep the North-East records apart from the all-India records: Dehing-Patkai and Jeypore, Mizoram and bamboo, jhum cultivation and sacred groves.
- Revise the montane sequence from the Terai and the foothills up to the temperate forests and the alpine pastures, so you can place any Himalayan tree correctly.
Common exam traps
- The tropical deciduous or monsoon forests, not the evergreen forests, cover the largest area of India.
- The Sundarbans is the largest mangrove forest of the world, but the question may ask instead for the largest rainforest of India, which is Dehing-Patkai.
- The National Forest Policy target is one-third of the land area, but the actual forest cover is only about 21.71 per cent.
- Jhum cultivation is shifting cultivation, and it is a cause of deforestation, not a method of conservation.
- Sacred groves are community-protected forests, so they are preserved by tradition and not by any forest law.
Frequently Asked Questions
How much of India is under forest cover and what is the National Forest Policy target?
As per the latest State of Forest Report, the forest cover of India is about 21.71 per cent of the geographical area, and the forest and tree cover together is about 24.62 per cent. The National Forest Policy of 1988 aims to maintain at least one-third, or about 33 per cent, of the total land area of the country under forest or tree cover, with a higher target for the hills. The North-East is the most forested region, with more than 65 per cent of its area under recorded forest.
What are the major forest types of India and which type covers the largest area?
The major types are tropical evergreen, tropical deciduous, thorn and scrub, montane and mangrove or littoral forests. The tropical deciduous forests, also called monsoon forests, cover the largest area, about 65 per cent of the total forest area of India. Rainfall decides the type: evergreen forests need more than 200 centimetres, moist deciduous about 100 to 200 centimetres, dry deciduous about 50 to 100 centimetres and thorn forests below about 50 centimetres.
Where are the evergreen, deciduous, thorn and mangrove forests found in India?
The tropical evergreen forests grow in the Western Ghats, the North-East and the Andaman and Nicobar Islands, with rosewood, ebony and mahogany. The deciduous forests, with teak and sal, are the most widespread. The thorn forests occur in the semi-arid regions of Rajasthan, Gujarat and Punjab with kikar, babul and khair. The mangrove forests grow in the deltas and coastal areas, and the Sundarbans is the largest mangrove forest in the world, with the sundari as its main tree.
What is special about the forests of the North-East and what threatens them?
The North-East is part of the Eastern Himalayan biodiversity hotspot and has more than 65 per cent of its area under recorded forest. Its people protect sacred groves, community woods preserved by tradition. The Dehing-Patkai forest is the largest rainforest of India and the Jeypore rainforest is famous for its Hollong trees, while Mizoram is the leading bamboo-producing state. The forests are threatened mainly by jhum cultivation, commercial logging and encroachment.
How do the montane forests of the Himalayas change with height and what is Van Mahotsav?
In the Himalayas the vegetation changes with altitude: the foothills have tropical wet deciduous and semi-evergreen forests, the Terai is known for tall grasses and sal, and higher up come sub-tropical and temperate forests of oak, deodar, pine and rhododendron, followed by alpine pastures and snow. The Eastern Himalayan belt is especially rich in sub-tropical and temperate species. Van Mahotsav is the tree-planting festival of India, celebrated in the first week of July, started to involve people in increasing the green cover.