PURE WOODS OR MIXED WOODS 1 195 



Different species make different demands on the locality, 

 not only as regards the chemical, but also, and chiefly so, 

 the physical conditions of the soil. Hence foresters divide 

 the species according to their demands on the fertility of the 

 soil. Some species, such as sycamore, ash, oak and elm, to 

 do really well, require a fertile soil ; others, such as chestnut, 

 beech and silver fir, are somewhat less exacting ; next come 

 Norway maple, lime, alder, larch and spruce ; less exacting 

 again are willow, poplars, birch, Weymouth, Scotch and 

 Austrian pine. As a general proposition it may be said that 

 heavy soils are better adapted for broad- leaved species, and 

 lighter soils for conifers. There are, however, exceptions ; 

 spruce, for instance, does well on heavy soils. A medium 

 class of soils, called loam, practically suits all species ; in the 

 same degree as the soil becomes heavier, broad-leaved species 

 should prevail, and vice versa. The final selection of the 

 right species is a difficult task, and the subject must be 

 studied in detail. 



Amongst the mountain and heath lands of this countr}^ areas 

 are, no doubt, found which can at once be j)lanted with the 

 more exacting species, but as the greater part of it has 

 deteriorated in consequence of long exposure, it will, in the 

 majority of cases, be advisable to let the first crop be a non- 

 exacting conifer, such as Scotch, Weymouth and Corsican 

 pine, and, in suitable localities, larch. These species will 

 gradually improve the land, so that they can be followed by 

 more exacting species. 



2. Pure Woods or Mixed Woods ? * 



The question, whether to grow woods consisting of one 

 species only, or woods containing two or more species 

 intermixed, presents itself to every proprietor and forester 

 in this country. Taste, as well as considerations based on 

 economic grounds, ditl'er much on this subject, and it seems 



* See pages 68 to 88 of Vol. II., tliird edition, of this Manual. 



o2 



