THE SHELTERWOOD SYSTEM 145 



8. In leaving special seed-trees, the ones of least 

 present commercial value are selected. 



9. Defective trees may sometimes be left as special 

 seed-trees, but only if they will produce seed in abun- 

 dance, and will stand long enough to secure reproduction. 



10. All groups and patches of immature timber and 

 young growth are carefully protected. 



11. Of no matter what size, trees attacked by insects 

 should be cut, even at extra expense, since this is the 

 only way to prevent the spread of insects to the rest 

 of the forest. 



In operating on these principles, care must be taken 

 not to injure the trees left standing. This applies to the 

 work of felling and of skidding out the logs. The for- 

 est is usually so open that there is no excuse for damage 

 in felling trees. Nor is there any reason for injuring the 

 standing trees and the young growth, especially if logs 

 are taken out by horse power. 



The Second Cutting. After reproduction has been 

 successfully secured, the forest is cut over a second time, 

 and the timber left from the first cut is removed. Theo- 

 retically, this cutting should take place as soon as the 

 young growth is thoroughly established. In actual prac- 

 tise, however, the second cutting cannot be accurately 

 timed with reference to the needs of the new growth. 

 This is particularly the case in extensive forests operated 

 on a large scale. Usually the second cutting will not 

 be made until the first cuttings have been completed 

 through the whole forest. Then the operations will 



