312 Fertilizers 



the different ones vary more or less in their character. 

 The trees of certain of them are long-lived, 40 years or 

 more, while others are comparatively short-lived 

 10 years or less. In certain of them the cropping period 

 is short ; the fruit ripens at once, while in others the ripen- 

 ing period extends over a considerable time. They also 

 differ in reference to their demands for plant-food, certain 

 of them requiring an abundance of available food, while 

 others can readily absorb the food necessary for their 

 growth from relatively insoluble compounds. In the 

 discussion, similar recommendations may be made in 

 many cases, though it is desirable that each class of fruits 

 shall be considered separately, and also that distinctions 

 should be made between what are regarded as good soils, 

 as medium soils and as poor soils, in respect to their content 

 of plant-food. 



THE GENERAL CHARACTER OF THE FERTILIZING 



It must be borne in mind, also, that inasmuch as the fruit 

 crop is not derived from annual plants, but from perennials, 

 the character of the feeding may be very different from 

 that in which the entire plant serves as a crop, as is the 

 case with the cereals and most vegetables. Hence, the 

 fertilizers applied need not all be of such a character as to 

 be immediately available. That is, the fertilizing mate- 

 rials may be such as to provide for a gradual and continuous 

 feeding. Those forms which decay relatively slowly are, 

 perhaps, quite as good, if not better, for many kinds of 

 fruits than those which by virtue of their solubility and 

 immediate availability are more stimulative in their char- 

 acter. Those fertilizers which do not contribute to the 

 immediate feeding of the tree or plant, but rather add to 



