i& PRACTICAL FORESTRY. 



or unfertile soils in accordance with the presence or 

 absence of one or more of the ingredients ; and in 

 accordance, too, with the amount of that vegetable 

 residue, 'the absence of which would render the most 

 perfect mechanical mixture of little cultural value. 



The agriculturist, dealing as he does almost entirely 

 with the top or surface soil />., the soil which has 

 been exposed to mechanical and climatic influences 

 can by inquiry find out what his soil contains, and. 

 also what the plant which he desires to grow requires, 

 and by adding the ingredient or ingredients which 

 are wanting grow pretty much what he desires. Not 

 so the arboriculturist. The subsoil to him is of 

 almost equal value, and will require his consideration 

 quite as much as the surface soil. Neither can he, by 

 adding chemical compounds, fit the soil for growing 

 trees otherwise unadapted to the purpose. 



It is nevertheless important that each should know 

 whether he is dealing with fertile clays, rich loams, 

 sandy loams, sands, or thin calcareous soils ; and also 

 know that all soils, of whatever nature, are formed of 

 clay, sand, and calcareous matter, in varying propor- 

 tions, and that in accordance with these proportions 

 we have clays, loams, sands, and marls, and other 

 intermediate classes of soils. 



Clays may be fertile or barren in accordance with 

 the plant-food which they contain, and in accordance 

 with their mechanical condition. If well drained, 

 they become a very storehouse of good things, and 

 arc the backbone of husbandry. If not, there is no 

 class of soil so useless. 



Loams are a mixture of clay and sand, and vary as 



