B. K. Sahay

Abstract

Indications are forthcoming that it is possible to predict the rainfall of a locality from a study of the comparative minimum water-levels of a lake or reservoir in the summer before the break of the monsoons.

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B. K. Sahay

Abstract

No abstract

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B. K. Sahay

Abstract

The problem of sal (Shorea robusta) regeneration in A₃ dry peninsular sal forests of Bihar, has been presented along with its growing importance in management. The Recruitment, as well as the Establishment stages of sal regeneration have been discussed in the background of well-known field results. Compaction of the top-soil is indicated to be contended against, for securing recruitment. Soil hoeing and soil working are suggested as interim measures, and the exclusion of forest fires, unrestricted grazing, surface exposure and desiccation, as the long-term measures for loosening the compacted top-soil and preventing the dehydration of the sal seed. Dying back of the sal seedlings in the pre-monsoon period, is stated to take place from March onwards. Moisture and ischolar_main competition at the peak of the growing season are indicated to be the limiting factors responsible for the dying hack of the whippy sal seedlings. Drastic fellings of the overwood, as well as the underwood, in one stage followed by cutting of the undergrowth for a number of years consecutively, just before the growing season, is suggested for the establishment of the whippy Sal seedlings. The importance of the cultural operations has been emphasized. The elongation of the ischolar_mains of seedlings is said to be dependent upon its moisture supply by sub-irrigation in the capillary fringe from perched or hanging water-table. The massive vegetation is stated to lower the water-table by transpiration losses. Further soil-moisture is depleted by ischolar_main-competition. The intensity of ischolar_main competition in the A horizon is supposed to increase rapidly with the age of the stand. The amount of available soil-moisture may be greatly increased by the elimination of ischolar_main-competition during periods of moisture stress of the growing season. Studies by various workers seem to confirm the conclusion arrived at in this connection. The elimination of all the transpiring plants seems to be the only remedy for conserving moisture in the period of drought which is also precisely the period of growth of sal seedlings.

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B. K. Sahay

Abstract

The assessment of natural regeneration of Sal (Shorea robusta) by sampling has been discussed. A number of sampling patterns under sampling intensities of 10 and 20 per cent have been constructed and the statistic derived have been tested against the actual deviations. A sampling intensity of 20% is indicated for assessing unestablished Sal regeneration in experimental plots of 1 acre. 10% seems to be the optimal sampling intensity for assessing. Recruitment and unestablished Sal regeneration in areas of the order of 2-4 acres. A lesser sampling intensity is indicated for assessing Sal regeneration of the same coefficient of variation in areas up to the order of small sub-compartments.

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B. K. Sahay

Abstract

No abstract

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B. K. Sahay

Abstract

Forest areas carry the worst type of soil and an erosive type of terrain which are in more need of intensive soil conservation measures than the waste and fallow-lands outside the forest areas. Overgrazing and recurring forest fires initiate compaction of soil and erosion. Natural regeneration cannot be secured under such conditions resulting in creation of innumerable blanks. This accentuates exposure and desiccation of the surface soil. Soil exhaustion is the most serious problem of soil conservation inside the forest areas. It is due to soil exhaustion that the pace of timber production is on such a low ebb. To combat this menace the soil conservation measures proposed in the Second Five-Year Plan inside the forest areas in Bihar have been enumerated.

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B. K. Sahay

Abstract

The management problems of sal (Shorea robusta) forests under conversion to uniform, selection and coppice workings have been presented along with the application of the sampling techniques for tackling the same. The forests under conversion to uniform are still stated to be far from a uniform fcrest. Determination of increment, structure and amount of growing stock is emphasized to be necessary. Laying out tree-increment plots as representative samples and their measurement in full is suggested for finding the increment. In order to check up the forecasts of growing stock and its structure by partial enumerations, it is suggested that the girth of trees be recorded and posted in control forms at the time of their feIlings. A regeneration sampling is advocated before clear-felling the sal overwood. Adoption of a financial rotation and its adherence is explained. The growing stock and increment figures of sal forests have been compared to the French and Swiss forests. The working of Biolley's methode du controle in Swiss forests has been described from a personal experience. The prerequisites of its adoption in other regions have been presented. It has been suggested to operate Biolley's check method through a set of representative samples-the linear increment plots. The specific problems of over-maturity and understocking of sal forests under selection working have been explained along with the need for adjusting to an optimum structure. Two characteristic features of the coppice forests, viz., their immaturity and understacking have been described. A lesser yield is advocated in favour of capitalisation. For contending against under-stocking it is claimed that sowing of sal seeds a couple of years in advance of the coppice fellings may suffice. The role of working plans in long term investigations on the quality and quantity of timber, on production and ecological trends of forests and on efficacy of silvicultural systems has been stressed. It has been emphasized that a working plan must ensure a continuity of its provisions in order to attain the dynamic equilibrium conditions of the forest with its size.

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