Practical Sylviculture. 609 



thiuiiing does not, as a rule, do very much harm, but ou steep or poor 

 soils a severe cutting out may ruin a forest. There are many points 

 to be considered Avhen a forest requires thinning, ;ind it is this that 

 makes it one of the most important forest Avorks, and on no 

 account should it be intrusted to any but trained men. As a rule 

 this operation is carried out far too severely, especially in young 

 forests where it ought to be light. The general rule is to thin lightly 

 in young growth, and increase the severity as the trees get older. 

 With regard to diseased trees, they should come out at any cost ; but 

 as to the removal of crooked ones care has to be exercised, a crooked 

 tree may be useless in itself, but its presence may be of the greatest 

 importance to its neighbors. 



The material produced by thinning can as a rule be sold, but 

 should no market exist it ought to be burnt, so as to prevent fungi 

 and insect pests getting into the forest. The stumps of the cut trees 

 should, if possible, be covered with earth for the same reason. 

 No other work is necessary till the forest is ripe for the axe, and 

 when that time arrives a system has to be carried out to meet not 

 only the market requirements, but also to insure, if possible, a 

 natural reproduction by seed, described in the first portion of this 

 article. 



