A il E R I C A X SYLVICULTURE 



A. Over-aged trees Iiave poor seeds. 



B. Interference iiirith the leaf canopy overhead at once 

 invites danger from fire, increased by the debris on the ground, and 

 by the impossibility of battling against fires in the vmderbrush. 



C. In the primeval forest, the age classes are usually mixed 

 in an irregular manner; uniform measures for reproduction are 

 therefore out of the question. The forester cannot generalize; he 

 must individualize, — a very expensive procedure in the face of low 

 stumpage values. 



D. The virgin forest nsually contains a mixture of 

 species; the best ones alone are removable; the weeds and the 

 worthless species are left on the ground; and from this fact arise' 

 additional difHciilties in the propagation of the most valuable kinds. 

 To this must be added the difficulty of properly guaging the light 

 and the shade according to the individualities of the species mixed. 



E. The lack of a permanent system of transportation 



in America necessitates the operations to extend at one stroke over 

 large areas, whilst natural seed regeneration requires tne gradual 

 removal of mother trees from small and restricted areas in imitation 

 of nature's own way of proceeding. 



As a matter of fact, the lack of permanent means of transporta- 

 tion in primeval Avoods is the most serious obstacle to the use of 

 regeneration from self-sown seed by a forester conscious of his aim 

 and its effect. 



F. Xatnral seed regeneration requires cutting, according 

 to the occurrence of seed years and according to the development 

 and the requirements of the young growth. The axe therefore 

 must be independent from the fluctuations of market or mill re- 

 quirements, — an impossible demand in the L'nited States at the 

 present time. 



The term '' natural seed regeneration " does not preclude the 

 use of artificial help to increase the chances of regeneration. The 

 term merely implies " seeding," or scattering of seed, in the main 

 unaided by man. Man, however, may carefully prepare the seed- 

 bed, by plowing or hoeing or digging, or may carefully press the 

 seeds naturally fallen into the soil; and may protect the seed and 

 the seedlings, at great pains, against external dangers. 



Little help is given, where soil and stiunpage are, and promise 

 to remain, of small value. 



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