314 FOREST PLANTING. 



and if we follow the hints pointed out herein by nature 

 we are able to cover rocky surfaces with vegetation much 

 quicker than nature does it herself. 



If only a small area with a rocky surface' is desired to 

 be planted, the ground should first be covered with 

 sods; and after the turf has become firmly fastened to 

 the rocky foundation, grasses, bushes, and even trees 

 may be grown thereon. But upon bare rocks of larger 

 dimensions this operation would be too expensive and 

 therefore we must look for other means to secure our 

 object. 



Kegularly the crevices and fissures of rocks, caused 

 by alternate freezing and thawing of the humidity that 

 enters the pores of the rocks, are first filled up with 

 mineralic particles on which plant growth is made 

 possible. These places have first to be taken up and to 

 be planted with suitable shrubs or trees, according to 

 the location and site of the place. The development of 

 the roots of the trees and bushes grown in those crevices 

 helps very much to promote the further disintegration 

 of the rocky surface and the accumulation of ingredients 

 upon which plants and trees feed. As soon as the sur- 

 face of the rock is sufficiently broken up into small 

 stones, which in time become embedded in some soil, the 

 operation of planting trees can be accelerated by mak- 

 ing horizontal terraces at convenient intervals, beginning 

 at the highest point of the place to be improved, and 

 securing the steep edges of the terraces by fascines or 

 wattled willow fences. It will not take a long time ere 

 the spaces between the edges of the terraces become 

 filled up by the further decomposition of the rocks and 

 stones, and then there will be room enough for planting 

 shrubs and trees. 



This is the only way in which rocky surfaces of 

 mountainous slopes, on which the mold has been 



