INTRODI T CTION 39 



Application of Silvicultural Systems 



If the conditions of the forest and those affecting lum- 

 bering are uniform, the forester may use a given system 

 over the whole forest. Thus, for example, in the Minne- 

 sota National Forest the land is flat and the logging 

 conditions are fairly uniform. The forest is also suffi- 

 ciently uniform to enable the application of one system 

 — the scattered seed-tree system — over most of the area. 



Usually conditions are variable, and a system applic- 

 able in one place is not suitable on other areas. Even 

 in the regular forests of Europe there are usually in each 

 forest several different silvicultural systems in operation. 

 In this country the forests are so irregular and the 

 logging conditions so variable that often in a single 

 logging operation more systems than one are used. For 

 example, in a forest chiefly of the selection character and 

 requiring the selection system, there may be patches of 

 even-aged timber which must be handled under one of 

 the other systems. In every case, the forester applies the 

 system best adapted to meet the special conditions under 

 which he works. 



Not only does the choice of a system of cutting de- 

 pend on local conditions, but the application of a given 

 system is subject to great variation. The application of 

 a given silvicultural system is dependent on the character 

 and condition of the stand and on the market and log- 

 ging conditions. 



Every species has its peculiar requirements for repro- 



