(]anadi(in Fon-shij Journdl. Scplcnihcr. 1917 1311 



AFFORESTING SAND DUNES IN CADIZ, SPAIN 

 (Z)e Castro, Manuel M. Fcrandez, in the Revista de Monies) 



The "navazos" form a characteristic method of improving sandy ground. 

 The author describes those at the mouth of the Guadalete on the pliocene 

 which, in the course of time has become covered with a sandy layer and trans- 

 formed into sandhills. The land was redeemed for cultivation by convert- 

 ing it into "navazos." It is possible to form a "navazo" wherever a shallow 

 and pervious soil overlies a sub-soil which is only slightly pervious, so that, 

 between the two, a layer of underground water is formed, which replaces 

 irrigation by rising under capillary attraction. In the locality under con- 

 sideration these strata are formed by the layer of sand and the pliocene re- 

 spectively. 



The land round the mouth of the Guadalete had been converted into 

 a series of "navazos" placed next to each other. As sand continued to form, 

 it at length became impossible to hold them any longer, and the abandoned 

 ' navazos' rapidly became sterile sandhills. It was then that the question 

 of afTorestation was considered. 



The afforestation was carried out in 1905 to 1913 under the direction 

 of the engineer Angel Fernandes de Castro by means of stone-pnes {Pinus 

 Pinea L.) 



In those parts of the "navazos" which have not yet been invaded by 

 sand, that is to say, in the ground that has been well manured by former 

 cultivation, the trees have grown with great force, so that some seven-year- 

 old pines have reached a height of over 16 feet, and there are annual growths 

 of nearly 5 feet. Growth is slower on the higher ground which separates one 

 "navazo" from another, but it is slowest inthe ground where the sand has 

 encroached. 



The work of afforestation gave opportunities for various experiments. 

 A group of closely planted trees was left to grow naturally, and it was found 

 that the lower verticils of the Pinus Pinea died off completely, that is to 

 say, a sort of natural pruning took place. Where trees were planted at nor- 

 mal distances from each other this natural pruning did not take place, and 

 it occurred still less where the trees were sparsely planted. In the latter 

 cases it is, therefore, wise to prune. Round Cadiz and Seville pruning is 

 carried out very energetically, and the small branches which are removed 

 are used for heating baking ovens. The pines which grow in abundance, 

 also supply wood for the construction of river boats and fishing smacks. 



HOW INDIA'S FORESTS PREVENT TORRENTS 



For over half a century, special laws have been passed in India for the 

 protection of hill catchment areas by making reserved forests and protected 

 forests. 



The examination of abundant material collected in all the Provinces 

 shows that the protective measures which were introduced during the last 

 decades, and carefully carried out, have decidedly prevented de-foresta- 

 tion in districts where the effects of the denudation of the country had be- 

 gun to be most severely felt. These measures were moreover taken at the 

 right time. During the first half of the 19th. century, the destruction of 

 the forests proceeded apace, as agriculture developed and villages increas- 

 ed. While the contractors cut down jungles, the villagers did still more 



