179- 



4) Safety from snow damage. All dense stands, and tall and 

 slender saplings, suffer regardless of the system used, so that protec- 

 tion from this danger is chiefly a matter of spacing to make the trees 

 resistant and become stiff. 



5) Frost hurts mostly in reproduction. The shelterwood is 

 best for the protection of young stands; the selection system also is 

 good. The clear cut system is not good, iilven coppice is bad with some 



s ecies. 



6) Insects attack all kinds of timber regardless of system. 

 They are worse in conifers than in hardwoods, and in the pure forest than 

 in mixed forest because each insect has its pet species, and takes the 

 whole stand. This is not so bad in a mixed stand. 



The site tells whether to use a pure forest. Most of these stands 

 are pure sind so tun right into danger. We have the choice of the clear 

 cut, shelterwood and selection systems. Large areas of young trees and 

 large bodies of old trees are more attacked. To avoid these conditions 

 use the selection or clear cut systems with the timber in small bodies. 

 The greatest damage is done to reproduction and to over-mature stands. 



