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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.
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.
All bamboo species growing in Bangladesh are closely
clumped except Melocanna baccifera where the culms are diffused.
The culm bears distinct nodes, hollow internodes, culm-sheaths, nodal
buds and branch complements. Generally from the point of view of utilization
bamboo means the culm, because matured culms are used most. New culms
usually develop from the rhizomes annually with the beginning of the rainy
season. The culm as it emerges from the undergound rhizome bud as a conical
shoot grows quickly. It reaches to its full height within a relatively
short time (30-60 days). Then the secondary thickness of cell walls take
place. It takes 2-3 years to become a matured culm. When matured the culms
become dull or yellowish in colour.
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]
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