64 FIRST BOOK OF FORESTRY 



shipment. Of old maple, birch, oak, and other hardwoods, 

 only about thirty per cent of all the wood is in valuable 

 logs, and seventy per cent is cheap firewood, while in 

 good pine or spruce over seventy per cent is usually cut 

 into valuable logs. 



In managing large pieces of selection forest it is best 

 to treat one part after another, and not to pick all over 

 the tract. Thus, if a man has sixty acres of such forest, 

 he would best cut over about five acres this year, five the 

 next, and so on, and in this way get over the entire sixty 

 acres every twelve years. This would give twelve years' 

 rest to the five acres first cut, during which time there 

 would be no cutting and dragging of logs and other mate- 

 rial, and at the same time the cutting would recur often 

 enough to keep the woods properly thinned and cleaned. 



STARTING THE YOUNG GROWTH UNDER SEED TREES 



In the selection forest old and young trees are mixed 

 in such an irregular way that it is difficult to know how 

 many trees there are a hundred years old, eighty years 

 old, etc. This makes it difficult to regulate the business 

 of the forest, to know how much is growing, to cut about 

 the same amount of the same kinds and of similar sizes. 

 Moreover, many a fine young tree thirty or forty years old 

 is damaged by the felling of a large neighbor, and many 

 good trees have to be taken out before their time because 



