MIXED CROP OF UNIFORM AGE. 43 



erode the soil, or bring in a deposit of silt, species producing suck- 

 ers will ordinarily not only maintain themselves, but even 

 increase their own proportion in the crop, and this the more easily, 

 the more destructive, within certain limits, the floods are. 



In the conditions of the First Case the saturation of the soil by 

 floods with saline substances was of slight or no importance in the 

 mutual struggle for existence. Here this circumstance acquires 

 its fullest sigificance, for whereas some species may be killed out- 

 right by the introduction of such substances, others may thrive as 

 as well as before, while a third class will suffer various degrees 

 of check in their growth. Thus babul is almost the only species 

 that can flourish in reh soil. In the Kheri Trans-Sarda forests in 

 Oudh, floods of the adjoining Soheli river have recently killed out 

 all the khair in the fire-protected low-lying block near Dudhua, 

 while young sissu are coming up in the newly deposited silt. Be- 

 fore fire-conservancy was introduced, the grass was all burnt in 

 the hot weather, and, in the absence of any obstacles, the annual 

 inundations quickly subsided without impregnating it with salts 

 to a sufficient extent to kill out the khair. 



(f) Action of man. All previous remarks on this head, except 

 what is purely referable to a mere difference of ages, have a much 

 wider application here, for there is much more room for selection 

 in a mixed than in a pure forest, and the action of man in the for- 

 mer must, on that account, have a considerably more far-reaching 

 as well as intensive influence. Before the introduction of conser- 

 vancy, teak was cut in the Central Provinces for the meanest uses, 

 and, except for fuel and for a few other special purposes, there was 

 no demand for any other species. In the interior of the Himala- 

 yas, deodar is, up to the present, the only tree removed on any con- 

 siderable scale. Centuries of dhaya have given an easy predomi- 

 nance to teak over large areas in Central India. In fact the 

 action of man, steadily directed with a single unswerving purpose, 

 may controvert the laws of nature to the utmost point to which they 

 may be defied. Indirect consequences of his action are also 

 manifest in forests, as for instance, the injurious effects of sulphur- 

 ous fumes emitted from neighbouring smelting furnaces. 



The extent to which a species can resist injuries resulting from 

 felling, conversion and export operations will depend 



(i) On its faculty of shooting up again from the collum of the 



root, or of throwing up suckers ; 

 (ii) On the firmness and strength of its roots ; 

 (iii) On the strength and elasticity of the trunk and branches ; 



