Silicon and carbon both belonging to
the fourth group in the Periodic Table
show similar chemical reactivity in many
respects. Both are able to form a series of
covalently bonded compounds, the bonds
being directed towards the corners of a
regular tetrahedron. DIMENSIONAL STABILIZATION OF WOOD
BY CHLOROSILANATION Silanes, corresponding to alkanes in
organic chemistry, have an empirical formula, Sin H2n-|-2O Each of the hydrogens
in the silane molecule may be substitute dby an electrophilic group, e. g., halogen or
by methyl groups. The properties of the organochlorosilanes are dependent on the

Programmes for extensive plantation
forestry have been taken by the Government
of Bangladesh to sustain the
adequate supply of forest products and to
maintain a balanced ecological condition
of the country. Large numbers of healthy
seedlings arc required for successful plantation
programme. Among the various
factors which threaten the production of
healthy seedlings, diseases play an important
role. Complaints regarding damage
of seedlings in the nursery by various
diseases are quite frequent. The present
investigation had been undertaken to study
the seedling diseases of eight tree species

Garjan (D. turbinatus) thrives very well in the hill forests under Cox’s Bazar
forest division. It also grows well in thE forests under Chittagong Hill Tracts,
Chittagong and Sylhet forest divisions. Uptill now Garjan has been extracted from
only the natural forests.

Experiments to determine the rok of
wounding alone and fungal infestation in
the formation of the aromatic base, agar,
in the wood of Agar tree (Aquilaria agallocha
Roxb.) were started in two Agar plantations
at Lawachara near Srimangal in
1977. Results of the first assessment of
nine trees after two years indicated that
the formation of agar did not depend on
the activity of a particular fungus, as was
previously believed, but is a general reaction
of the host to injury and invasion by
various microbes. It was, therefore, suggested
that the effect of wounding on the

Forest tree species are generally propagated from seeds, seedlings and stumps.Vegetative propagation from roots and shoot cuttings is another technique by which identical propagules could be perpetuated and proliferated.

Grafting, cutting and air-layeiing are the basic techniques of propagation and
are very useful for tree breeding and improvement work. The importance of
vegetative propagation is gradually increasing for establishment of Seed Orchard and
Clonal Orchard (Jones 1979).

Since long past offset and rhizome
planting have been conventional methods
of small scale bamboo propagation in the
villages of Bangladesh and other
neighbouring countries (Peal 1882). Use of
these propagules, however, is not economic
for large scale bamboo afforestation
programme due to their bulky size, heavy
weight (4-30 Kg) and transportation
problem (Banik 1980). Moreover, a clump
can supply these propagules in only limited
numbers, certainly not enough for large
scale plantation. The availability of bamboo
seeds is also restricted because of long
flowering interval in bamboo. Propagation
of bamboo through branch cutting

A kraft mill, even by utilizing the best available technology,
cannot be made completely odour-free. However, there are several
sulphide-free and non-sulphur pulping methods. Among these, sodaanthraquinone
(AQ) pulping process seems to be promissing.

The most practised chemical to-day is the kraft process. 95% of the present production of chemical 74 Pulp yield can be increased by using polysulphide, H2S or AQ
in the cook. The first two are used exclusively in kfraft cooking, and
so the odour problem cannot be overcome. AQ on the other hand,
is also suitable in a sulphur-free cook which eliminates the odour
problem of the pulp mill. Soda-AQ pulping is more suitable with
hardwoods.

Seedlings of Pinus caribaea var.
hondurensis planted at Keochia Silvicultural
Research Station, Chittagong in 1972
reached an average height of 14.0 m and
started bearing fruits in 1982. The trees
flowered during the months of January-
February and cones ripened in August-
September of the same year. Some seeds
were hand-picked from two selected trees
in 1982 and the seeds were extracted from
the cones by exposing them in the sun.
Germination experiment was carried out
with them. The seeds were first tested by
floatation process with 85% ethyl alcohol
for finding out the empty seeds. After the
test, 220 mature seeds were sown in
polybags filled up with forest top soil. An
appropriate quantity of chemical fertilizer
was also applied. The tops of the bags

Garjan (JDipterocarpus spp.), by virtue
of its availability and strength properties,
happens to be the principal species for
railway sleepers in Bangladesh. This
species is used also for construction and
many other purposes. The wide and
extensive use of this species has created
scarcity and its present supply position is
not adequate to meet the requirement of
sleepers. As a result, sleepers are being
imported from foreign countries to overcome
the supply shortage. It is, therefore,
necessary that other suitable indigenous
species be used as railway sleepers.
Although there are more than 500
hardwood species in the forests of
Bangladesh only a few of them are available
in quantities commensurate with the
requirements of the timber industries. In order
to find out a group of alternative timber
species for sleepers a joint study was undertakenby
Forest Research Institute, Bangladesh
Railway and Forest utilization Division

Loranthaceae includes semiparasitic
plants which are commonly known as
mistletoes. All over the world they cause
more economic loss than any other angiospermic
parasites. They mostly attack
dicotyledons and gymnosperms which
include horticultural plants as well as forest
trees. The effects of parasites on the hosts
are manifold, such as, reduction of vigour
and growth rates, poor fruit and seed
production, formation of burrs on the trunk
or branches, reduction in foliage, drying
of top, predisposition to insect and other
disease attacks ultimately causing premature
death. In tropical and sub-tropical
forests, mistletoe infection sometimes causes
heavy damages to many forest trees.