88 



ARID AGRICULTURE. 



if water is never allowed to touch the crowns of 

 the plant. Some crops should not he irrigated 

 at certain stages of growth unless absolutely 

 necessary to save them. Experience tells the 

 farmer when his crop is suffering for water and 

 no general rule can he laid down. Short season 

 crops may be ripened early by keeping water 



/ ^ 



'&T- J 



Plate XIII. Hanover Canal in Winter. 



