Bangladesh in general possesses a luxuriant vegetation, with villages appearing to be virtually buried in groves of mango, jackfruit, bamboo, betel nut, coconut, and date palm. Bangladesh has four different areas of vegetation. The eastern zone, consisting of parts of the Sylhet and Chittagong areas, has many low hills covered with jungles of bamboo and rattan (a species of climbing palm). The most common plant is a large kind of bamboo that is the basis of the country's paper industry. The central zone, covering parts of the country extending north of Dhaka, contains a large number of lakes and swampy vegetation; the soil of part of this zone is laterite, which produces the Madhupur jungles. The area lying to the northwest of the Brahmaputra and to the southwest of the Padma forms a flat plain, the vegetation of which consists mostly of cultivated plants and orchards. Babul (Acacia arabica) is the most conspicuous plant. The southern zone along the Bay of Bengal contains the Sundarbans, with their distinctive mangrove vegetation. In this vast forest grow many commercially valuable trees, such as the sundri, for which the Sundarbans are named (Heritiera fomes or minor); gewa, or gengwa (Excoecaria agallocha), a softwood tree used for making newsprint; and goran (Ceriops roxburghiana), a type of mangrove. Among the astounding variety of flowers are the shapla (water lily), the country's national flower; the marigold; the lotus jasmine; the rajani gandha (a tuber rose); the china rose (jaba); the flame of the forest; and the bokul (Mimusops elengi).
Most of Bangladesh was originally forested from the delta up to the hills, with coastal mangroves backed by swamp forests and a broad plain of tropical moist deciduous forest. However, most of the original vegetation has been cleared and less than five percent of the original cover remains. According to FAO estimates the annual deforestation rate is 80 sq. km. per year. Patches of rain forest only survive in the Chittagong regions in the southeast, where four hill ranges run parallel to the coast. The country's principal remaining forest heritage is the Sundarbans, a massive area of mangrove forest, 75 per cent of which lies in Bangladesh and 25 per cent in India. Bangladesh has three main forest formations:
1 The hills were once covered by tropical evergreen and semi-evergreen rain forest. Remnants of these forests are found in the eastern part of the country in the Chittagong Hill Tracts, Chittagong, Cox's Bazar and the Sylhet Forest Division.
2 Tropical monsoon forests in Bangladesh are known as the Sal forests after the main timber tree, Shorea Robusta. At one time they covered relatively small areas of the inland plains of the Madhupur Tract. Relicts are still found in the Dhaka, Tangail and Mymensingh Forest Divisions and some badly managed patches survive in the north.
3 Tidal forests (mostly mangroves) are located mainly in the Sundarbans on the southwest of Bangladesh and small areas in the Chittagong district.
Some 4,000 sq. km. Of evergreen, semi-evergreen and mixed evergreen forests in the Sylhet, Chittagong, Cox's Bazar, Chittagong Hill Tracts North and South Forest Divisions along the eastern side of the country, are reserved forests. Tall tree, 30-45m high, including Dipterocarpus spp.,Swintonia floribunda, Mangifera longipes, etc. being moist deciduous form the top canopy. The second storey is evergreen and includes Hopea odorata, Mesua ferrea, Amoora wallichi, Syzgium spp. etc. the undergrowth often includes pure formations of bamboo's (mainly Melocanna bambusoides) or a mixture of bamboo, canes, palms, orchids and ferns. Clear felling of the forests is completely destroying this fine ecosystem.
The Tropical Monsoon Forests or Sal Forests covers some 300 sq. km. in the Dhaka, Jamalpur, Mymensingh and Tangail Forest Divisions. This is dominated by Shorea robusta, Adina cordifolia, Terminalia spp, Albizia spp, etc. there is no virgin sal forest. What is surviving today represents rather coppice stage. The rate of encroachment of sal forest land lumber poaching are threatening the last remaining good sal tree stands of the Madhupur Tract, embracing areas of the forest of Mymensingh and Tangail divisions. The entire sal forest is threatened with extinction, as this is located in the most thickly populated districts of the country.
The country's principal remaining forest heritage is the Sundarbans, a massive area of mangrove forest, 75 per cent of which lies in Bangladesh and 25 per cent in India. It's total area is about 6,200 sq. km. including the innumerable canals and rivers traversing through the forest. The dominant plants are Heriteria fmes, Excoecaria agallocha, Avecinnia spp., Sonneratia spp., Phoenix paludosa, Nipa fruticans, Hibiscus tiliaceus, Pandanus odoratissimus, Acanthus ilicifolius, etc. The mangroves are managed for timber production and wildlife conservation. The Sundarbans serve many purposes, including providing substantial quantities of fuel wood and building timber. They are the only refuge of the Bengal Tiger.
The village groves have mango Mangifera indica, jackfruit Artocarpus heterophyllus, coconut Cocos nucifer, date palm Phoenix sylvestris, palmyra palm Borassus flabellifer, betel-nut Areca catechu, several species of bamboo and figs, blackberry Syzgium cumini, citrus fruits, Albizia spp., Bauhinia spp., Erythrina spp., Polyalthia longfolia, Streblus asper, Lantana camara, Eupatorium odoratum, Mikania scandans, canes and banana plants.
The natural and man made coastal forests in the districts of Barisal, Noakhali, Patualkhali and Chittagong are comprised of Avicennia spp., Agialitis rotundifolia, etc., covering some 500 sq. km. or so. Recently the vegetation in the coastal belt (other than the Sundarbans) has increased due to a forestation program taken up by the Forest Department to protect the coastal areas from tidal surges.
