An experiment was conducted to find the suitability of 28 miscellaneous hardwood species in mixtures for the manufacture of particleboard. The species were grouped into five specific gravity classes in increasing order based on the specific gravity of individual species.

The average density of the boards of Specific Gravity Class I (667 kg/m³) made from low specific gravity species is less than that of the boards of Specific Gravity Class V (705 kg/m ) made from medium and high specific gravity species but the strength ofthe former (178 kg/cm²) was observed to be higher than the latter (107 kg/cm²). The average strength of the boards of Specific Gravity Class V does not satisfy the ‘standard’ for medium density boards. Species of high specific gravity may be used in the manufacture of medium density board by mixing the chips oflow specific gravity specjes. The thickness swelling (22-35 %) of the boards of all groups was observed much higher than the optimum. This may be reduced by increasing the amount of solid content of UF glue and adding water repellent in the chips during the manufacture of boards.

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.

A study was made on the emerging culm mortality of eight different bamboo species of Bangladesh. Mortality percentage varied from species to species and even from clump to clump. Average mortality percentage varied from 28 to 69 in the case of thick-walled and large dimension bamboo species, and 9 to 37 in the case of thinwalled, small dimension species.

Eco-physiological conditions and genetic make-up of each species and clump seem to influence the rate of mortality of emerging culm in bamboo.

Air-layering on Dhakijam (Syzygium grande Wt. Wald.) and Garjan (Dipterocarpus turbinatus Gaertn. F.) was done in sapling and adult trees with coconut fibre warp and polythene warp. Adult trees responded better than saplings in respect ofrooting. Higher percentage of rooting was observed with coconut fibre warp than with polythene warp. The maximum success achieved in adult trees of Dhakijam and Garjan was 96 per cent and 56 per cent respectively. Rooted air-layered ramets were collected and planted in 30×45 cm poly.hene bags in the nursery for further establishment.

A collaborative study was undertaken to find out suitable indigenous timber species alternative to Walnut for manufacture of rifle butt. Various properties like,; anatomical, physical, mechanical, machining, treating and finishing, of five potential species were studied and compared with those of Walnut. A time-dependant kiln schedule was developed for seasoning the alternative species in a single charge. The assembled rifle butts of all these species were subjected to the standard service and endurance tests. The results indicate that Gamar,
light coloured Champa and Teak may be used along with Chickrassy for manufacture of rifle butt.

Of the 10 M  m² of raw hides produced annually in Bangladesh only a fifth is tanned by 175 odd tanneries, using imported tanning materials. Vegetable tannins can be extracted from roughly 10,000 tors of mangrove barks available annually at the felling coupes in the Sundarbans. Amelioration of the properties of these tannins is, however, a precondition to their use as tanning materials.

Tannins were extracted by various methods from goran (Ceriops decandra), kankra (Brugiera gymnorrhiza) and passur (Xylocarpus molluccensis) barks collected from the Sundarbans. The percentages of tannins obtained were 24, 21 and 17 respectively. A method was developed for overall purification and improvement of colour and quality of tannin. Chemical analysis indicates that the tannin is of catechol group and quantitative analysis of the extractives shows that the production of mangrove tannins would be an economically viable proposition. Tanning experiments with goat skin show that light coloured and fine-grained uppers and soles can be made with the purified tannins.

Fibre dimensions of Pinus caribaea, Leucaena leucocephala, and Acacia auriculiformis were studied to assess their suitability for making paper pulp. The results obtained with Pinus caribaea grown in Bargladesh were comparable with those in the literature. The fibre dimension characteristics of Leucaena leucocephala predicted the suitability of the spec’es for pulp making. Acacia auriculiformis showed similar fibre properties with those of civit.

A germination test was carried out to observe the effect of salinity on germination performance of seeds of kcora (Sonneratia apetala Bach.-Ham.). Increasing waler salinity caused a decline and delay in germination. Highest
germination success was recorded at 5 ppi and no germination occurred above 40 ppt. Salinities around 10 ppt appeared to be optimal for raising nursery beds of S. apetala along the coastal belt.