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remunerative remains to be seen, but in 1911 the Deputy Conservator of 

 Forests in charge of the Sind circle recorded the following opinion : ' These 

 schemes are bearing beneficial results, but in my opinion their total cost, 

 together with the large annual outlay required to maintain them in efficient 

 order, will be found in the future to be out of all proportion to the revenue 

 likely to be yielded by the forests concerned. These irrigation schemes are 

 complicated in many instances by the necessity on the one hand of protecting 

 adjoining cultivation from forest flood water, on the other hand of not inter- 

 fering with the customary water supply of cultivation beyond forest limits, 

 and lastly by the difficulty of draining most of the forests so irrigated, at the 

 close of the flood season. When and if a solution of these difficulties can be 

 found, it almost invariably implies greater expense, both capital and recurring. 

 I would therefore recommend that all inland forests should be gradually 

 discarded whenever opportunities occur of acquiring riparian areas instead, so 

 as to maintain undiminished, and to increase if possible, the total area under 

 forest, while at the same time abolishing the difficulties, expense, and inter- 

 ference with more legitimate forest duties entailed by complicated schemes 

 of irrigation.' 



The alluvium of which the plains of Sind are formed consists of varying 

 proportions of sand and clay, from pure sand to clayey loam. In places not 

 subject to annual flooding patches of saline soil known as kallar often occur : 

 such soil is produced by the evaporation of subsoil moisture containing salts 

 in solution, resulting in the exudation of a whitish efflorescence on the surface 

 of the ground, while the soil itself is usually darker in colour and moister 

 than the normal soil. Babul does not grow on this saline soil where the salinity 

 is at all marked ; it gives way to tamarisk, which in turn yields to Salvadora, 

 while finally chenopodiaceous plants such as Suaeda fruticosa and Salsola 

 foetida mark the last limit of vegetation when the salts become too concentrated 

 for the existence of other species. 



Acacia arabica is far more plentiful in lower Sind than in upper Sind. 

 In the latter it is replaced to a great extent by the hardier Prosopis spicigera, 

 owing no doubt principally to the greater intensity of the frost, the climate 

 of lower Sind being milder owing to its proximity to the sea ; also the duration 

 and extent of the river inundations is greater in lower than in upper Sind, 

 and this further influences the distribution of the babul. 



The most important associates of the babul in Sind are Tamarix dioica 

 and T. Troupii, which are capable of standing soil conditions both too moist 

 and too dry for the babul, but thrive well along with it ; Populus euphratica, 

 which appears on new alluvium along with the babul ; and, to a lesser extent, 

 Prosopis spicigera. The last-named species usually appears when the land has 

 become elevated above the reach of all but abnormal floods, and as a rule 

 indicates a failing water-supply ; it is, however, also frequently met with in 

 areas suitable for babul except for a dense growth of grass, the presence of 

 Prosopis in place of babul being due to the greater power of resistance to 

 suppression possessed by the former. Occasionally Tamarix articidata also 

 appears with Prosopis. As the ground becomes drier Salvadora oleoides, S. 

 persica, and Capparis aphylla make their appearance. Among other species, 

 some of them introduced, which are occasionally found in the babul forests 



