APPLICATION OF THE METHOD. 91 



silver fir in sandy soils. Occurring scattered through- 

 out the forest, and towering above a complete under 

 story of the other trees, the pines like oak in broad- 

 leaved forests find a soil that is always moist with- 

 out being damp ; their crowns overtop those of the 

 auxiliary species, and spread out on every side ; they 

 are well furnished with leaves, and the woody tissue 

 is well nourished. It is a matter of fact, too, that 

 there is not so much danger of insects as in crops 

 of pure pine. 



When the Scotch pine is growing absolutely pure, 

 it will be best to commence the introduction of beech 

 or silver fir, according to local conditions, under 

 crops that have attained the age of forty or fifty 

 years ; but we must not overreach the object in 

 view, and the proportion of the tree we introduce 

 must be regulated accordingly. 



The Scotch fir is a species that may be termed an 

 invader, and notably in the forest of Haguenau, it 

 has supplanted the broad-leaved trees, thanks to 

 clear cuttings. In these soils, which are too rich 

 for it, its regeneration is made more difficult, owing 

 to an abundant growth of grass. It should there be 

 made gradually to give way to the oak, which in that 

 forest yields the most valuable produce, while the 

 pine, being at its extreme southern limit in the 

 plains, yields an indifferent quality of timber. 



Hitherto but few cases have occurred where re- 

 generation of this pine associated with other trees 

 has had to be undertaken, but where such a case has 

 occurred, the regeneration cuttings were conducted 

 (and rightly so, as it would seem, since the results 



