MXIXTENAXCE OF THE SELECTION METHOD, 179 



Wd "which it takes of the ground gives it au advantage over 

 tlie latter species, in that individuals of it, reserved far apart when 

 the older growth has been removed, are safe against injury from 

 winds. 



Moreover the detailed treatment of the various species referred 

 to in the preceding paragraph is different for each of them. Thus 

 ia order to obtain a crop of seedlings of the silver fir, the spruce 

 and the beech, it is an excellent precaution to prune off the lower 

 branches of the trees a few years before they are felled ; for the 

 pines and the larch, the same end is served by a slight or partial 

 working up of the ground, which, by loosening the soil where it is 

 exposed to the liglit, furnishes the best means for sowing the 

 ground. Such are the principal cultural operations, extremely simple 

 as they are, that are required in a forest worked by Selection. 



The risk attending the Selection Method, when it is badly 

 carried out, or removes too many trees from a given area, 

 is not less great in pine forests than in those of silver fir, in 

 iarch forests than in those of the spruce. It is most 

 to be dreaded at high elevations, precisely there where the 

 Application of that Method is always necessary and demands great 

 skilL At such elevations, where extreme cold prevails, the years 

 of seed are few and far between ; the summer, which brusquely 

 succeeds the winter, often injures germinating seeds and younw 

 seedlings ; and, lastly, the forests suffer severely from atmospheric 

 influences, chief among which is the wind. 



Under these peculisur conditions two opposite series of pheno- 

 mena may be met with. Where the land is partially covered with 

 young forest growth, such as scattered seedlings, patches of thickets, 

 and bouquets of saplings, the cover thus formed becomes more and 

 more effective every year as the forest developes, and the moisture 

 of the soil is better and better preserved during the summer. 

 Vegetation is active, the sparse crop meets and closes overhead, 

 and soon the forest completely covers and takes possession of the 

 ground. On the other hand when the forest growth, composed of 

 old or middle aged trees with lofty crowns, begins to thin itself 

 naturally and let in light everywhere over a certain area, the trees 

 ar« d^ffiv^d of the mutual support which they gave each other. 



