50 The Principles of Fruit-growing. 



"Here the drying effect of the wind at 300 feet 

 was 30 per cent greater than at 20 feet, and 7 per 

 cent greater than at 150 feet from the hedge. 



"When the air came across a clover field 780 

 feet wide, the observed rates of evaporation were: 



"At 20 feet from clover 9.3 cc. 



"150 " " " 12.1" 



"300 " " " 13. " 



or 40 per cent greater at 300 feet away than at 

 20 feet, and 7.4 per cent greater than at 150 feet. 



"The protective influence of grass lands and the 

 disadvantage of very broad fields of these light soils 

 was further shown by the increasingly poorer stand 

 of young clover as the eastern margin of these 

 fields was approached, even on fields where the 

 drifting had been inappreciable. Below are given 

 the number of clover plants per equal areas on 

 three different farms, as the distance to the east- 

 ward of grass fields increased: 



"No 1, at 50 feet, 574 plants ; at 200 feet, 390 plants ; at 400 feet, 

 231 plants. 



"No 2, at 100 feet, 249 plants ; at 200 feet, 277 plants ; at 400 feet, 

 193 plants ; at 600 feet, 189 plants ; at 800 feet, 138 plants ; at 1,000 

 feet, 48 plants. 



"No. 3, at 50 feet, 1,130 plants ; at 400 feet, 600 plants; at 700 

 feet, 543 plants. 



"In these cases the difference in stand appears 

 to have resulted from an increasing drying action 

 of the wind. On the majority of fields the de- 

 structive effects of the winds were very evident to 



