120 INDIAN FOREST MEMOIRS. 



This is exactly what fire really does and it appears to act in two principal ways : — 



(1) By directly destroying the humus which may exist in the surface soil and by 



effectually preventing any further addition to the existing supply through the 

 destruction of all dead leaves and organic debris. 



(2) By altering the character of the clayey constituents of the soil in such a way 



that loam to a great extent loses its power of retaining water. The texture 

 of the soil becomes coarser and percolation is increased. 



The grassland known as Gola Tappar in the present locality which is shown in Plate 

 XL is believed to be an instructive example of this drying action of fire on the soil. This 

 grassland is believed to occupy ground which was at one time covered with Sal forest, the 

 latter having been cleared for cultivation. The soil is a loam, apparently suitable for Sal 

 and more or less similar to that in the adjoining Sal forest which surrounds the area on all 

 sides, while Saccharum Narenga, the Sal-locality-indicator, is a common grass in the area. 

 This 1 Tappar is reported to have been regularly burnt for many years and the result is 

 remarkable. Instead of a dense growth of the giant Saccharum Narenga which would 

 naturally have been expected in such a locality we find a good deal of both Saccharum 

 Narenga and Saccharum Munja, but only of very inferior vigour and dimensions, while 

 more significant still, we find the xerophilous Andropogon contortus actually able to occupy 

 considerable areas and to become dominant in a locality where it would, under ordinary 

 circumstances, have been ousted by the far more vigorous competitors named. Experience 

 elsewhere in similar soil has shown that fire is not likely to have here caused the poor growth 

 of the Saccharum sp. noticed, by direct injury to the plants and both the species here flower 

 freely which would not be the case if the direct fire damage was severe and most of the one- 

 year culms destroyed. It is therefore concluded that, in this case, the poor growth of the 

 coarse savannah grasses and the unusual prevalence of the more xerophilous Andropogon 

 is mainly due to the drying of the soil and that this area affords a good example of the 

 power possessed by fires of replacing hygrophilous, or strongly mesophilous growth, by a 

 xerophilous type of vegetation. It has often been stated that fires favour the development 

 of coarse species and are injurious to the more valuable fodder grasses. From the above 

 remarks, however, it will be seen that such a generalisation is impossible, that fire under 

 certain circumstances can kill out a coarse, comparatively valueless, fodder-grass like 

 Saccharum Munja and may cause it to be replaced by a more valuable fodder-species like 

 Andropogon monticola and that, as a general rule, by its action in drying the soil, fire is 

 able to produce conditions favourable for comparatively xerophilous species which are 

 usually more valuable for fodder than the hygrophilous or strongly mesophilous grasses. 

 In areas where the latter prevail it must I think be accepted that firing is, on the whole, 

 decidedly beneficial in improving the fodder supply. Further than this, however, it is 

 impossible to generalise for, when dealing with the xerophilous or less strongly mesophilous 

 species, it is obvious that some are of more value as fodder than others and that 

 some are avoided by cattle on account of their peculiar taste, odour, cutting leaves, 



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