CHAPTER I 



THE WATER REQUIREMENTS OF FRUIT PLANTS 



There is more or less acknowledgement of a difference in adaptability 

 of different fruits to varying moisture conditions in the soil; this is, 

 however, expressed in terms of tolerance more often than in terms of 

 requirements. It is stated frequently that sour cherries will stand a 

 dry soil or that pears will endure a wet soil; there is very little exact 

 information on what the various fruits actually require. Table 2 gives 

 some interesting results of investigation in California on the requirements 

 of fruit and other crops under conditions common in that section. The 

 requirements of the several fruits stated in terms of the amounts of free 

 water in the soil, exhibit a considerable difference. Other data to be 

 introduced later (Tables 11 and 12) show that the same fruit may have 

 different moisture requirements in different localities. 



Table 2.- 



-Relative Water Requirements of Different Plants 



(After Loughridge^'') 



/ Water as a Plant Constituent. — Water is a normal constituent of all 

 plant tissues, comprising from 50 to 75 per cent, of the leaves and twigs, 

 from 60 to 85 per cent, of the roots, and 85 per cent, or more of most 

 fleshy fruits. 



