A high degree of dimensional stability was obtained by epoxy treatment of Corsican pine (Pinus nigra) wood. It was found that the degree of dimensional stability was strongly and positively correlated with the level of substitution obtained. The dimensional stability obtained was of permanent nature and was practically unaffected by quite severe simulated weathering. The introduced material was in the cell wall and probably covalently bonded to the same.

The wood specimens, chemically modified by propylene oxide under 10 bar Na pressure and 130°C temperature for 90 minutes, were tested for sorption at various relative humidities. Typical isotherms for normal pine wood were also found with controls, whereas, a noticeable change in the isotherms was observed with modified specimens. At low values of RH the treated specimens absorbed and retained less moisture than the controls. Above about 55 % RH the modified wood started to absorb increasing quantities ofmoisture and in the 95-100% RH region the EMC of treated wood was slightly greater than that of controls.

Reduction, in the degree of swelling of treated specimens compared to that of controls was reasonably constant throughout the sorption range. High moisture sorption at high levels of RH was not accompanied by a corresponding increase in dimensional change. Large water uptake was probably due to the rigid bulky propane chains retaining the cell walls in a swollen but relatively porous state. Treatment with propylene oxide, thus, led to significant improvement in dimensional stability throughout the hygroscopic range.

An experiment was designed to observe the effect of tending treatments on the growth and development of Teak (Tectona grandis L.) saplings in Andermanik forest, Chittagong, in 1978. It was noticed that great variations existed among the plants after five months of planting. Close examinations suggested that the variability was related to the size of Teak stumps planted. This variability had a marked effect on survival and early development of the plants.

This work includes the determination of moisture content, bulk density, shrinkage, drying properties and strength properties of Coconut wood. It also incorporates some of the findings of other countries. All the properties indicate that Coconut wood offers an excellent possibility of its use in round form as well as in converted form. The strength values of Coconut wood suggest that it can provide necessary materials for low cost housing. The lower part of the bole may be used for making furniture and utility items, while both sawn and round wood may be employed for transmission poles and posts. Thus Coconut wood may serve as an alternative to wood-raw material.

Tiger population of the Nilkamal Sanctuary was studied in 1982. The population size was determined by studying the pugmarks and faeces. Information was also collected from local people and forest staff. The total number of tigers in the Sundarbans is estimated to be at best 460.

Sundri (Heritiera fomes) poles were treated with 40 : 60 creosote and light diesel oil mixture at different pre-designed combination of treating pressure and treatment time to evaluate the response to the individual as well as combined action of these process variables. It was found that the effect of treatment time was statistically highly significant in increasing the penetration of preservative into the sapwood while the treating pressure could increase the same only significantly. On the other hand, both the treating pressure and the treatment time had highly significant effect on increasing retention of preservative in the sapwood.

The coefficient of variations of penetration and the coefficient of variations of retention within the individual poles were in the range of 2.14 to 22.56 percent and 2.15 to 14.75 percent respectively. The same for among the poles were 30 and 23 percent respectively. The variation in these characteristics of the pole, however, could not be considered disadvantageous because the penetration and the retention were directly correlated with the thickness of sapwood zone in the poles.

Seasoned Sundri pole without being subjected to any pretreatment conditioning could be treated to achieve 2.85 cm penetration and 373.22 kg/m² retention in the sapwood after using a treating schedule of 10.55 kg/cm² treating pressure and 6 hours treatment time. This amount of penetration and retention may be considered adequate for poles to be used in power transmission line in Bangladesh, as these are well above the minimum recommended in the Bangladesh Standards for penetration and retention for such use.

The paper evaluates the Teak (Tectona grandis Linn.) plantation programmes of Bangladesh in order to develop a suitable strategy for its long-term planning.

The percentage of Teak plantation in Cox’s Bazar, Chittagong, Chittagong Hill Tracts (North), Chittagong Hill Tracts (South) and Sylhet Forest Divisions stands at 28, 20, 14, 14, and 12 respectively. 1-14 year and 15-29 year plantations constitute 48% and 45%
respectively.
The marginal value growth percent in good Teak plantations comes close to zero beyond 40 years. The ratio of basal area growth of non-Teak species to Teak in the mixed plantations of age 33 to 55 years ranges between 1.36 to 2.40 indicating that Teak grows poorly compared to many other species. Yield data have been compared with those of other Teak growing countries. It is concluded that there should be no plantation in sites worse than SI 30.

Assuming per capita consumption of 0.10 m³ and population growth rate as much as 0.30%, total Teak requirement by 2040 a. would be about 1.05 lakh m³ which amounts to 5% of total output. The required plantation area should lie between 3 and 5 percent only. The existing proportion of 70% is not economically justified. Five strategies with respect to sites, rotation, thinning and stocking are pointed out in order to make long-term programme consistent with socio-economic goals and national forest policy.

Fibre dimensions of various wood, bamboo and grass species and miscellaneous fibrous materials of Bangladesh have been studied from time to time in the Pulp and Paper Division of the Forest Research Institute, Chittagong. The data from these studies have been compiled in this review and the species have been graded as very good, good or poor for paper making on the basis of Runkel ratio. Two other properties, viz., flexibility co-efficient and relative fibre length have also been determined, since these properties are reported to be correlated to the tensile strength and tearing resistance of paper. Out of all the species studied, 33 wood, 3 bamboo, 2 grass & 4 miscellaneous species have been found promising for paper making.

Gluability of a veneer species is a function of the strength and durability of plywood. Champa has been one ofthe chosen decorative species for veneer. An investigation was made to find the gluability of Champa compared to that of Civit, a species having excellent gluability properties. Champa veneers peeled to 1.0 mm thickness and dried to 8% target moisture content were bonded with liquid UF glue catalysed with 2% hardener and extended with 20% wheat flour to make 3-ply plywood panels. The dry shear load and wet shear load of Champa plywood compared favourably with those of Civit plywood and the values were well above the minimum requirements. Therefore, plywood made from Champa veneer bonded with U F glue may be recommended for use as Warm Water Resistant Grade.

Vegetative and floral morphologies of the monotypic genus Melocalamus compactifloras (Kurz) Benth. have been described. Detailed morphology of the fruit and seed has also been investigated. Its relationship with Melocatma Trin. and Dinochloa Buse has been established as proposed by Dransfield ( 1981 ).

Keora wood was pulped by steaming the chips under 10 kg/cm² and 7 kg/cm² pressures each for half hour, one hour and one and half hour. The pulps were refined to two different freenesses in each case. Hardboards were made from these pulps without using any sizing materials or additives and tested for strength and water absorption properties. The boards were moderate in strength and water resistance.