SNOWBREAK. 



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The following table gives von Seelen's observations on 

 damage by snow in December, 1883, in the Hasselfeld forest 

 range. 



c. System of Management. 



As the species which suffer most from snow are grown in 

 high forest, that system is most liable to snowbreak. 



Woods, where the trees in each compartment are of even 

 age and height, suffer more than uneven-aged woods, such as 

 those grown under the selection system ; in the former case, 

 snow may lie in masses like a flat roof over the crowns of the 

 trees, especially when the wood is densely stocked, whilst in 

 uneven-aged woods the snow has a greater surface to cover, 

 the tree-tops being irregular in height, and more snow reaches 

 the ground by falling between the crowns of the trees. In the 

 second case, the wind also enters the wood more freely and 

 shakes the snow from the crowns of the trees. 



Hence, in localities liable to snowbreak, the selection and 

 group systems are more suitable than other high forest 

 systems. In coppice-with-standards, the lanky tellers occa- 

 sionally suffer soon after a felling. Pure coppice is rarely 

 injured by snow. 



d. Age of Wood. 



Slowly growing species such as silver-fir, spruce and beech 

 are most endangered by snow between the ages of 20 and 60 

 years, quickly growing species such as Scots pine and larch 



