104 



REVIEW OF THE INFUENCES OF WINDBREAKS UPON FRUIT 



PLANTATIONS. 



The benefits derived from windbreaks are numerous, posi- 

 tive 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 windbreak 

 when they escape injury in other places. This fact is easily ex- 

 plained, however. The influence of a windbreak upon the tem- 

 peratures 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 temperature. It ac- 

 quires. 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 accelera- 

 tion of evaporation ; and winds which are no colder than the 

 given area, if comparatively dry, may consequently do great dam- 

 age to fruit plantations. This is particularly true at certain times 

 during the winter season. Land winds, being cold and dry, are 

 therefore apt to be dangerous, while winds which traverse large 

 bodies of water, and are therefore comparatively warm and moist, 

 are usually in themselves protectors of tender plants. The follow- 

 ing table, giving the average temperatures of different winds at 

 New Haven, Connecticut, as compared with the mean tempera- 

 ture of that place, shows that those winds which blow off the 

 Sound' are much warmer than the land winds* : 



Loomis' Meteorology, 88. 



