786 JOURNAL OF FORESTRY 



though the majority of young plants may dry up after the stand is 

 removed, enough seed comes in from the sides to furnish seedlings, 

 filling in and insuring regrowth. That is, providing the cut is not too 

 broad and wrongly exposed to the wind. 



THINNINGS 



Thinnings have been carried on for a long time, but until recently 

 they were mostly light and moderate, or so-called "low" thinnings, and 

 have not influenced the growth as much as the newer forms of so-called 

 crown thinnings. The general practice is to thin as soon as the wood 

 output will pay for the trouble. In southern Sweden it might begin 

 cjuite early or at any rate after thirty years, when the wood obtained 

 can be used for making charcoal ; but in the north it may be consider- 

 ably later, especially if the wood can only be used as pulp wood (which 

 might be taken to about 4 inches d.b.h.). Broadly speaking, it has been 

 the custom to consider thinning up to 10 per cent of the stand's volume 

 as "weak" or "light," 10-15 per cent "medium," and 15-25 per cent 

 "heavy," if the thinnings are repeated every fiz'e years. 



The most modern principle is to keep the stands well closed until 

 the trees begin to drop their lower branches, then to increase the 

 degree of the thinnings, returning every 10 years for a cut of 20-30 

 per cent "from" above," that is, with most attention directed toward the 

 crown conditions. As opposed to the old practice_, the "crown thin- 

 nings" aim first at giving the finest trees of the dominant classes better 

 chance to develop by giving them room and light ; then also, quite 

 unlike what one used to do, to spare harmless young suppressed trees 

 which keep the ground covered and in good condition by hindering 

 the growth of undesirable vegetation which might establish itself 

 after the thinning owing to the greater intensity of light. One is more 

 and more convinced that the severer thinnings are going to prove more 

 advantageous. In conclusion one may say that, from a silvicultural 

 standpoint, thinnings keep two main objects in mind: (1) to maintain 

 or increase the growth in value; (2) to keep the ground in good con- 

 dition, especially before the final cut and regeneration. 



LOGGING 



The logging proper is invariably preceded by the marking and 

 estimating of the tract, by a crew of two or three workers directed 

 by a tally man. They may take sample trees to determine the volumes 



