The lack of knowledge of treatability of timber species with pressure method may result in poor treatment in respect of penetration and retention of the preservative chemical Inwood. This knowledge for our indigenous timber species was not ascertained before. The relative penetrability of nineteen timber species was, therefore, determined with Lowry empty cell process using 40:60 creosote and light diesel oil mixture.

Specific gravity of species did not seem to have any bearing on the penetration cf preservative. Grain structure and presence of tyloses  appeared to be correlated with penetrability of the wood. The species were classified into four treatability groups according to the degree of heartwood penetrability.

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Paper pulps have been prepared from Gamar (Gmelina arborea, Roxb.) wood of four age groups by the kraft process. Cooks were made with active alkali and sulfidity ranging from 14,94 percent to 21.05 percent and 14,12 percent to 20,12 percent respectively at 170° C, The best pulp was obtained with 16 years old gamar wood at 14,94 percent active alkali and 14,57 percent sulfidity under optimum condition. Pulp-yield varied from 40,86 percent to 49,35 perecnt at various ages. The physical strength and other properties of Gamar kraft pulp compared favourably with those of other hardwood pulps prepared in the Forest Research Institute, Chittagong.

Teak fruits were experimentally graded by weight and graded according to size This gave a total 35 weight-cum-size grades of fruits The germinative and the average seedling production capacity of the fruits of each grade were tested. It was found that the results were influenced by the way the data were arranged and produced. The weight-cum-size arrangement showed confused, unexpected and unnatural trends which were difficult to explain but the size-cum-weight arrangement showed a linear relationship between size of the fruit and the number of seeds which was according to expectation and in conformity with the results reported earlier It has, therefore, been concluded that size of the fruit is primary and the weight is only secondary in determining the quality of Teak fruits. Grading of Teak fruits by combining size and weight can give fruit lots upto 50-75 percent germinability and average number of 1.00-2 50 seedlings per fruit.

Excepting bamboo and sungrass, various grass species growing in the forest lands of Chittagong, Chittagong Hill Tracts and Sylhet districts of Bangladesh, at present, have practically no use. Five grass species, namely, Panicum, antidetale, Retz., Themeda arundinacea, Ridley., Saccharum spontaneum Linn., Thysanolaena maxima, O Ktze, and Imperata arundinacea, Cyr., which are available in the area in appreciable quantities, have been pulped by steaming and soda processes for the manufacture of insulation boards in equivalent mixtures as well as in the proportion of their availability in the forests. The pulps obtained by the steaming process were free-draining but rather dark in colour. Soda pulps were lighter in colour but comparatively slow-draining. Yield was high in both the processes.

Rigid structural insulation boards were made both by press-drying in a hot hydraulic press at low pressure and by cold pressing the mats and then drying in a force-draft oven. The boards had very good strength but moderate heat insulating properties, They compared favourably with the imported ones so far as the moisture resistance properties were concerned.

It has been found that the nature and time of flowering In pineapple can be improved by treating the plants with hormones. The most obvious effect has been found to be enhanced flowering both in terms of time and quantity.  The response of the plants to hormone treatment varied according to the substances used and their concentration. Other effects of hormone treatment have been found to be increase in size and weight of the fruit.

Bamboo bllght causing severe mortality particularly of young culms, in the village groves of Rajshahi district of Bangladesh is reported. A brief history of the outbreak of the disease is noted, A review of bamboo diseases is provided. Symptoms and observed mode of infections are recorded. Four fungi have been isolated from diseased bamboo samples. The pattern of isolation strongly suggests that Conlothyrium fuckelil Sacc. is responsible for the blight.

The paper critically discusses the methods so far developed for determining the best rotations (years from planting to final cutting) for forest plantations in order to help professional forestry personnel to determine the appropriate growing periods for Bangladeshi forest stands. It is observed that most rotation models which are in use place a lot of emphasis on the needs of wood producers. The needs of the industries and other users generally receive less attention, Recent developments abroad have attempted to rectify this situation. It should be borne in mind, however, that no single method can be considered to meet all our needs even for public investment purposes. We are suggesting means to select the models consistent with maximum economic growth resulting from income and employment effects on the nation as a whole. The analysis also presents techniques to decide the time of the final cutting decision at the end of the predicted rotation in view of specific changes in the economic climate and other conditions.

Rhizome assemblies and clump form and growth of nine arboretum grown bamboo species have been studied. Rhizome stalk has been found to play an important role in determining the form, shape and growth of clumps. This is due to not only the characteristic length of the stalk in some species but also its role in orienting the rhizome in relation to the centre of the clump and the mother culm in general and the line of gravity in particular. In areas where bamboos are worked heavily it is the rhizome stalk that is first affected and may result in congested clumps in species otherwise monopodial or loosely tufted. Rhizomes are commonly attacked by pathogenic soil ganisms, Parts like rhizome stalks, whole bud of the rhizome may be partly or wholly consumed or otherwise become inoperative and although these parts contribute to the development of rhizome assembly they do not contribute towards the growth of clump. This reduces the rate of growth of clumps considerably. Irrespective of species, only 8 percent of the buds develop into normal culms, 77 percent remaining dormant and 15 percent are damaged by pathogenic soil mlcrooganisms. It has been concluded tha- application of antipathogens individually or in combination with fertilizer will ameliorate the conditions of growth and considerably increase the outturn.

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