HERMAN H. CHAPMAN 53 



bution of their age classes, and are composed of many 

 species, some of which are not valuable, he is sometimes 

 forced by market values to do just what he ought not 

 to do, that is, cut the best kinds and leave the poorer. 

 But the difference between his operations and the lum- 

 berman's would be, that he would make every effort to 

 cut out and get rid of as much poor material as he could 

 sell, even at a very small profit, and save as many of 

 the more valuable trees as he could, both to grow and 

 to act as seed trees. The form of a forest cut on these 

 principles is bound to be very irregular and patchy. 

 But most of our native woods, especially our virgin stands 

 of hardwood, are of this character, and it would not be 

 possible to at once bring them into the condition when 

 the stands are comparatively even-aged. There is young 

 timber in scattered bodies all through the forest, which has 

 been growing for 10 to 50 years, and this must be allowed 

 to mature. But on the whole, the aim of the forester in 

 most cases should be to work for even-aged stands rath- 

 er than to try to perpetuate a selection form of many- 

 aged stands indefinitely. Greater yields are produced 

 by the even-aged form, and the expense and difficulties 

 of logging are much reduced. 



Changing a Selection Forest to an Even-Aged Form. 

 A good example of the choice between these two ex- 

 tremes is to be found in stands of western yellow pine. 

 This tree is so nearly fireproof and wind-firm that it is 

 hardly ever destroyed. The old trees die singly and 

 groups of young trees take their place. The whole form 

 of the forest is open on account of the dryness of the 

 soil. It would be perfectly possible to apply a selection 

 system of cutting here, removing a few old trees each 

 year. But the reproduction of the tree would take place 

 just as well over large cleared areas if seed trees were 

 present, and the expense of logging is such that it is ab- 

 solutely necessary to cut as much from each acre as the 



