INTRODUCTION xv 



other details of cultivation have been repeatedly 

 tested. 



In forestry it is different. In many cases there 

 is no past history of the land which can give assist- 

 ance to the forester. There is no knowledge of 

 the capacity of the site for growing timber, gained 

 by the experience of many crops of timber on 

 that land. A landowner may know that a plot 

 of land is apparently such as is usually suitable 

 for certain trees, and that these trees are usually 

 planted of a certain size and distance apart, 

 but he has no past experiments to guide him in 

 deciding how far the general rules should be 

 varied to meet the local peculiarities of his own 

 land, and whether the land is really as suitable 

 for timber as it seems to be. 



Forestry is an art, the rules of which cannot 

 be stated with precision. Rules may be of 

 great value. A forester who has an adequate 

 knowledge of the methods by which success has 

 been obtained by others is more likely to be 

 successful than another man of equal ability 

 who has no other guide than his own experience. 

 But no rules can apply accurately to the local 

 peculiarities of different properties. Success in 

 forestry mainly depends on personal observation 

 and practical sagacity. It is a great mistake 



