



•2 ■^'.w* - *^ • 



r^Q0^. 



Planting Pine Trees on Steep Slope 



whole has been done. The French 

 people are now suffering from a mis- 

 take for which they were not to blame. 

 They could not foresee, when they in- 

 augurated the idea of giving the indi- 

 vidual an absolutely free hand, that the 

 individual would destroy the forests, 

 nor did they know at that time that 

 even if the forests were destroyed such 

 disastrous consequences would follow. 



Ill 



The work being done in those lofty, 

 rugged mounains to prevent the 

 ordinary small and harmless streams 

 from becoming raging torrents, which 

 cut away the mountain sides and carry 

 the debris down on to the fields be'ow 

 each time a heavy rain occurs or the 

 snow melts, is intensely interesting. 



The work is really of two distinct 

 kinds, the first consisting of engineering 

 feats in checking the force of the tor- 

 rents and preventing them from wash- 

 ing awa^' the slopes and carrying down 

 large quantities of debris, and the 

 second consisting of gradual reforesta- 

 tion of the slopes in order to eventuall} 

 make the engineering work unnecessary. 



The first work is absolutely essential 

 because, until the streams have been 

 held in check and the slopes prevented 

 from continually slipping, reforestation 

 is impossible. When the slopes have 

 been given a certain degree of perma- 

 nence, reforestation is begun by first 

 planting strips of grass and willow in 

 horizontal lines around the slope. When 

 the success of these strips gives rea- 



sonable assurance that there will proba- 

 bly be no more slipping, the final step 

 of planting the slope with trees, chiefly 

 pine and larch, is taken. But until the 

 forest has finally become firmly estab- 

 lished, there is the continual danger 

 that the engineering work will be torn 

 out by an unusual freshet and the whole 

 work have to be done over again. Sev- 

 eral cases where this occurred were 

 seen. 



The basis of the engineering work is 

 the "barrage," a dam of dry stone or 

 mortar masonr}' built in the bed of the 

 stream. The first work on any stream 

 consists of placing a series of these 

 "barrages" at certain regular intervals 

 in the stream bed in such a way that 

 the profile formed by a line along their 

 spillways will give the angle of slope 

 which it is desired the stream bed shall 

 have. These "barrages" fill in above 

 with debris so that if successful they 

 actually form part of the stream bed. 

 The type of "barrage" varies greatly: 

 but in general those on the upper slopes 

 are small and built of dry stone, 

 whereas those in the lower part of the 

 stream are built of dressed stones and 

 mortar and are larger and much more 

 costly. 



IV 



Tn order to show more clearly how 

 this work is done, the difficulties 



20I 



