198 FOREST PLANTIKG. 



When, in the course of time, the soil is increased in 

 quantity and quality, we must endeavor to plant more 

 valuable trees. At all events, upon slopes whose pitch 

 exceeds forty yards descent in the one hundred, the 

 high-forest system is the only rational one, and in stock- 

 ing with young trees, we should, if the nature of the sur- 

 face permits, prefer the species having long tap roots, 

 which will bind the soil better. 



The proper time to build these dams is, of course, 

 during the season when the waters flow least or not at 

 all. They must be very strong in order to successfully 

 resist the force with which the headwaters, in times, are 

 precipitating themselves into the valleys. It is, there- 

 fore, advisable, instead of building a few high dams in 

 great distances from each other, to construct as many 

 as possible low ones. For it is the intention to use these 

 dams not only to obviate the fury of the downward 

 streaming waters, but also to catch up every particle of 

 fertile soil which is being carried below, and thus to 

 make the soil remain in the more elevated parts of the 

 mountains. In order to make the dams strong and last- 

 ing, the basis and sides of the same must be protected 

 by fascines, hurdle work or even by rocks and mason 

 work. 



This is the way in which the memorable work for re- 

 stocking the denuded woodlands upon the Alps of 

 Southern France has been achieved, and by which the 

 former frequent and pernicious inundations of the rivers 

 there for the last ten years have been prevented.* It 

 is true the costs have been enormous, but a single inun- 



* The best book on this subject is written by the French Over-forest 

 Master Demontzey, who conducted for nearly thirty yeai-s the work of 

 re-foresting and retm-fing denuded woodlands in Algiers and France. 

 The full title of this book is : " Demontzey F. TraiU praiiqtie dw reboiae- 

 ment et du gazonnement de» montanges. Hois, 1882." 



