CHAPTER II: PROTECTION AGAINST STORM, EROSION, 

 SANDDRIFTS, NOXIOUS GASES. 



Part 12. Protection Against Wind Storms. 



WIND is BENEFICIAL: 



By restoring the chemical balance of the atmosphere; 

 By distributing pollen and seeds; 

 By preventing excessive formation of side branches; 

 By bringing rain. 



A. DAMAGE is CAUSED BY WIND STORM (aside of forest fires spread or fanned) : 



(a) IN PLANTATIONS: 



By loosening the anchorage of tall seedlings and 

 saplings; (notably, after planting in furrows, 

 in the prairies, on sand dunes); 



By drying out roots and shoots and leaves and 

 soil (notably in the early spring); 



By removing the protecting cover of snow; 



By allowing the "mob" to whip the top shoots 

 of "aristocrats." 



(b) IN EXPOSED LOCALITIES: 



By one-sided (seashore or Pisgah ridge) or stunted 

 growth. 



(c) IN TREE FORESTS AND IN LARGE POLE WOODS: 



By breakage of crowns or branches, thus allow- 

 ing access to fungi and to insects; 



By breakage of stems at their point of least re- 

 sistence; 



By uprooting trees singly, in avenues, or in large 

 blocks; 



By endangering the logging operations. 



B. FACTORS OF DAMAGE ARE: 



(a) SPECIES: 



Flat-rooted conifers are most endangered; a mix- 

 ture of species in advisable. 



(b) SIZE CLASS: 



Poles and trees over 8" in diameter are most 

 subject to damage. 



(c) LOCALITY: 



Leeward sides of lakes; 



Mountain slopes and mountain tops on leeward 



side; 



Moist spots; 

 Shallow soil. 



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