influences of Wind-breaks. 79 



upon the patches of wild berries. It is not often, 

 however, that the forest areas become a very serious 

 menace to fruit-growers. 



Review of the influences of wind-breaks upon fruit 

 plantations. The benefits derived from wind-breaks 

 are numerous, most positive in character, and appear 

 to possess sufficient importance to warrant the 

 strongest recommendations of horticultural writers. 

 Yet the injuries occasionally sustained in consequence 

 of shelter belts may be serious, for it is a well 

 attested fact that trees sometimes suffer from cold 

 in the immediate vicinity of a dense wind-break 

 when they escape injury in other places. This fact 

 is easily explained, however. The influence of a 

 wind-break upon the temperatures of an adjacent 

 plantation is governed by its position with reference 

 to prevailing or severe winds. Of itself, wind 

 probably exerts little or no influence upon tempera- 

 ture. It acquires the temperature of surfaces over 

 which it passes. If these surfaces are colder than 

 the given area, cold winds are the result, or if 

 warmer, as a large body of water, the winds are 

 warm. But wind often causes great injury to plants 

 because of its acceleration of evaporation; and winds 

 which are no colder than the given area, if com- 

 paratively dry, may consequently do great damage to 

 fruit plantations. This is particularly true at cer- 

 tain times during the winter season. Land winds, 

 being cold and dry, are therefore apt to be danger- 

 ous, while winds which traverse large bodies of 

 water, and are therefore comparatively warm and 



