3i LOCALITY AND FOREST VEGETATION. 



moisture and the condition of the soil during the growing 

 season, as set forth in the following arrangement : — 



JVet sail : Water flows from it without the application of 



pressure. — Even in summer water runs off in drops on 



the application of pressure. 

 Moist .sail : On pressure being applied, water falls in 



drops. — During summer the soil does not become dry 



beyond one inch below the surface. 

 Frc'sJt soil : Leaves traces of moisture on the palm of the 



hand on being pressed. — During summer it does not 



become dry beyond six inches below the surface. 

 Dnj suil : Has lost the dark colour due to the presence of 



moisture, but does not fall to dust on being broken. — In 



summer it becomes dry to a depth of 12 inches within 



a week after a good soaking rain. 

 Arid soil : Falls to dust on being broken. — In summer it 



dries up to a depth of more than 12 inches within a few 



days after a good soaking rain. 



Section' IY. — Effect of the Soil li-on Eohest 

 Vegetation. 



In estimating the efifect wliicli differently constituted soils 

 have upon forest vegetation, and more especially ui)on tree 

 growth, the forester is guided by the demands made by the 

 trees upon the soil. Ordinarily the soil sliould provide the 

 tree with : — 



(a.) Stability. 



{b.) Space for a suitable spreading of the root system. 



{<:.) Moisture, in suitable quantities at all times. 



{(l.) Nourishing substances, in sufficient quantities and in a 

 condition suitable for absorption by the roots. 

 Any soil which meets these requirements is fertile for sylvicul- 

 tural purposes, and experience has shown, that fertile forest 

 soil must possess the following properties : — 



(J.) A sufficient depth. 



