Bamboo

Bamboo (bash) any of the tree-like tropical and subtropical grasses of the family Poaceae (=Gramineae) having a hollow, woody stem. As they have tree-like habits, sometimes they are treated under a different family, Bambusaceae. But most of the botanists prefer to keep it under Poaceae. Bamboos have an extremely wide range of global distribution. They are of enormous importance to the rural people of Bangladesh, and are extensively used for house construction, scaffolding, ladders, mats, baskets, traps, handicrafts, etc and several other articles of everyday use. In some parts of the country the bamboo leaves are used as thatching materials and fodder.

Bamboo clump

For tropical countries bamboo is one of the important raw materials for paper industries. They are also grown for hedges and landscaping. Bamboo groves also act as a wind-break and prevent soil erosion. The young tender shoots of bamboo are eaten as delicious vegetables. These young shoots, locally known as 'banskorol' are a favourite food of the tribal people of the chittagong hill tracts during the rainy season. Considering the wide range of uses as construction materials it is called the "poor men's timber". Most bamboos are large and complex plants that remain in a vegetative state for many years, have flower only occasionally. Bamboos have an erratic flowering habit and flower at long intervals. The flowering cycle ranges from 3-120 years, and in most cases between 15-60 years. Most of the bamboo species die after gregarious flowering.

In Bangladesh 26 species and one variety of bamboo under 7 genera occur both in wild and cultivated states. Bamboo species growing in forest areas are Bambusa burmanica, B. polymorpha, B. nutans, B. tulda, Dendrocalamus hamiltonii, D. longispathus, Melocanna baccifera and Schizostachyum dullooa. M. baccifera grows in pure brakes, while the others grow sporadically in small patches. Natural bamboos occur in eastern hill forests of the country. Common village bamboos are Bambusa balcooa, B. cacharensis, B. comillensis, B. jaintiana, B. nutans, B. salarkhanii, B. tulda, B. vulgaris, and Thyrsostachys oliveri. Bamboos propagate both through seeds and vegetative means. When the bamboo flowers, it produces seeds (except B. balcooa and B. vulgaris). Matured seeds germinate in nature or when raised in nurseries.

The seedlings look like paddy or wheat seedlings. The most traditional vegetative propagation method is offset planting. A lower part of a single culm with the rhizome axis basal to it is an offset. Offsets are collected just before the monsoon (April-May) and planted with the onset of the monsoon. An offset becomes a matured harvestable clump in three years. Top dressing with soil and paddy husk to clumps is a mode of management. There is no remarkable pest or disease damage except top dying of B. balcooa and B. vulgaris.

While in external use as posts, fences, etc termites and fungi destroy bamboo in about one or two years. If treated with preservatives bamboo may last for 15 years. CCB (copper sulphate, sodium dichromate and boric acid in 2:2:1) solution is a good preservative. Bamboo is treated in two different methods, namely sap displacement and soaking with this preservative. [M Khairul Alam]

Muli bamboo (mooli bash) A close relative of the common bamboo of the grass family Gramineae, Melocanna baccifera. The culm of the muli bamboo reaches 10 to 20 metres in height and the diameter ranges from 1.7 to 7.5 cm depending on the age. Leaves are light green, long and spear-shaped. The leaf sheath is thicker. Young culms are green and gradually turn yellowish with ages.

Muli bamboo grows naturally in the forests of the Chittagong, Chittagong Hill Tracts and Sylhet. The plant grows well all over Bangladesh except the mangrove forest.

Use of the muli culm is diversified. It is extensively used in the construction of thatched houses by the poorer section of people of Bangladesh. Varieties of handicrafts and even low-cost furniture are also made with this species of bamboo. This species is extensively used for the paper and pulp industry and for the production of rayon. [Abul Khair]