EFFECTS OF ITS REMOVAL. 605 



length of faggot-wood, cutting off the needle-bearing twigs from 

 ever}' branch with a bill-hook. 



Section V. — Effects of the Removal of Litter. 



Continuous removal of litter is prejudicial not only to the 

 vitality and productive power of forests, but also to the fertility 

 and amenity of countries, owing to the important action of forests 

 on their physical conditions. 



1. Effects on Forests. 

 (a) Ground-litter. 

 i. General effects. 



When the soil-covering of litter and humus is allowed to 

 decompose uninterruptedly, it returns to the forest soil the 

 chemical elements of which it has been deprived, enriches it 

 with carbon-dioxide and prepares it for absorbing and retaining 

 all the nourishment requisite for the growth of trees ; it 

 maintains in the soil a suitable condition of porosity, admits 

 moderate supplies of air, and finally, protects the soil against 

 extremes of heat and cold. Nature has thus permanently 

 supplied the soil not only with the materials but also with the 

 forces necessary for the nutrition of trees. If these beneficial 

 influences are withdrawn from the soil, circumstances are 

 considerably altered. The soil becomes chemically poorer; 

 owing to unimpeded evaporation it loses more and more that 

 degree of moisture which is essential for the growth of trees ; 

 the supply of carbon-dioxide to the soil is greatly reduced, so 

 that the process of forming humus and the consequent pro- 

 duction of solvents for its mineral substances are arrested. In 

 a word, the soil loses the power of producing trees, becomes dry, 

 hard and dead, this eventually occurring even when a soil is 

 chemically rich. 



The soil of agricultural lands is partly an artificial product, 

 being b}' artificial means rendered porous and well supplied 

 with manure, water, kc. ; forest soil, on the contrary, depends 

 solely on the climate and tree-growth for maintaining its own 

 productive powers, receiving nothing from outside ; it must 

 therefore be protected against the diminution or destruction of 



