126 INDIAN FOREST MEMOIRS. 



overhead shade and diffuse lateral illumination than when grown in the open 

 with no shade. 

 (c) That sal is decidedly sensitive as regards soil-aeration and water-logging proves 

 rapidly fatal. 



These results therefore show that sal is only likely to establish itself on well-drained 

 soil which is not subject to water-logging and that in this locality any factor which reduces 

 the humus content of the soil, or which tends to increase the loss of moisture from the soil by 

 evaporation, tends to retard the establishment of sal reproduction. 



The burning of grasslands which it is desired to ultimately afforest with sal therefore 

 is obviously injurious owing to the destruction of all humus and organic debris while on the 

 other hand the introduction, where possible, of plants like Eugenia operculata, Adhatoda 

 and Mallotus into these areas will almost certainly accelerate the establishment of sal 

 owing to their power of increasing the humus content of the soil, their shade being also 

 to some extent beneficial. 



106. It must of course be understood that the 

 above remarks apply to the locality more particularly considered in this paper and it is 

 obvious that the conditions prevailing here and in the Sal forests of Central India are very 

 different from those of some of the Sal tracts of Bengal and Assam where the tree has 

 extended into, or close to, the hygrophytic Zone of the tropical evergreen forest. In such 

 places the dominant factor is frequently not lack of sufficient soil moisture, but the presence 

 of more vigorous competitors, and it is possible that fires, by reducing the water-content of 

 the soil, may be beneficial to the Sal by rendering the conditions less favourable for the 

 vigorous development of its injurious hygrophilous competitors. In these localities, also, 

 insufficient aeration of the soil may in some cases be responsible for the unsatisfactory 

 growth of Sal seedlings and here again firing would probably be beneficial. 



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