566 PROTECTION AGAINST SNOW. 



between the ages of 15 and 30 years. Thickets 1 to 20 years 

 old withstand snow better owing to their elasticity, and woods 

 over 60 years old suffer less, on account of the greater size of 

 the trees, although in Thuringia 60 to 100-year-old woods 

 have suffered severely. A distinction must, however, be 

 made between bending and breakage. Bending owing to snow 

 is most frequent in woods 20 to 40 years old, and occurs 

 generally in patches. 



Snowbreak, on the contrary, is most frequent in woods 

 40 to 60 years old and even in older woods. The crown and 

 leading snoots of the trees are chiefly broken in woods up to 

 60 years old, whilst in older woods branches are broken off the 

 stem. In otherwise uninjured woods, stem-breakage is 

 generally near the base of the crown and occurs here and there 

 to individual trees. Younger drawn -up stems are often broken 

 in groups, and sometimes in strips, owing to the action of 

 wind during or after the fall of snow. 



In the extensive snowbreak which happened in the Harz 

 forests in December, 1883, trees of the following categories 

 were injured in following proportion for the whole area 

 affected : 



Age of Woods Percentage of 



in Years. Breakage. 



2030 . ..-/;. . . 10 



3040 . . ... . 25 



4050 . . . ' '. . . 25 



5060 . . , . ... 20 



6070 . . . . . . 12 



7080 . : . . '.., .... . 5 



80 and over ... . . 3 



e. Locality. 



Mountain-forests are more affected by snowbreak than 

 forests of the plains and lowlands. The localities in Germany 

 most exposed to snowbreak lie between altitudes of 1,300 and 

 2,400 feet ; the snow falls more abundantly at higher eleva- 

 tions, but then the flakes are smaller and drier, and do not 

 become so readily attached to the trees; lower down, on the 

 other hand, the fall of snow frequently changes into rain. In 



