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General Manures. These are such as, owing to their complex com- 

 position, contain all the varied substances that have been removed from 

 the land by crops or the grazing of animals. The only one, however, 

 that fully deserves the title of general fertilizer is farm-yard or stable 

 manure. This fertilizer consists of a mixture of the liquid and solid 

 excreta of animals with straw that has been used for litter. As a 

 matter of course, this material will vary to some extent in composition 

 and value, according to the nature of the animal, the food it has been 

 fed upon, and the proportion of straw it contains, but all the essential 

 matter for plant food will be there more or less. A compost formed of 

 a mixture of vegetable and animal substances makes a fertilizer only 

 second in value to farm-yard manure. In addition to their direct value 

 as fertilizers, general manures have a physical and chemical effect on 

 soils which should not be overlooked. The decomposition of the 

 vegetable and animal substances produces carbonic acid in large quan- 

 tities, which acts upon other materials in the soil and sets them free for 

 the use of plants. These manures also have a useful mechanical action 

 upon soils, by making them more open, and favouring the admission of 

 air. 



Special Manures. These may contain one, two, or more of the 

 essential constituents of plant food, but not all. They are a useful 

 class, and may often be used with great advantage to supply the soil 

 specially with some material which it lacks. Though these deficiencies 

 may be made good by general manures, yet they can often be more readily 

 and economically supplied by special fertilizers. The principal of the 

 special manures required in fruit culture are lime, bone-dust, potash, 

 soda, magnesia, phosphoric acid, and silica. But before using these 

 materials, the cultivator must know exactly what his soil requires, 

 otherwise he may do more harm than good. Though special manures 

 are effective and economical when properly used, yet it will be a waste 

 if they are not required. It is not well to supply lime to land that is 

 already rich in that material, or potash to soil that contains plenty of 

 that mineral, and so on. First ascertain the soil deficiencies, and then 

 these fertilizers may be utilised to advantage, but not otherwise. As 

 will be seen by an examination of the table showing the essential 

 mineral matter removed from land by various crops, that fruits vary 

 considerably in their requirements. Some kinds, such as the Grape, 

 Olive, Plum, Peach, Pear, Apricot, and Cherry, take up potash in very 

 large quantities. This is why these fruits often thrive to perfection in 

 volcanic soils. An ample supply of potash is, therefore, a primary 

 requirement with all these fruits. The Orange, Lemon, Fig, Olive, and 

 Plum require lime in large proportions, and this material is abundant in 

 many soils. Phosphoric acid is required in very large proportions by 

 the Almond, Quince, and Lemon, and also to a considerable though a 

 lesser extent by the Plum, Pear, Cherry, Orange, Strawberry, and 

 Apple. 



The principal artificial manures that may be used with advantage in 

 fruit culture are as follows : 



Lime. This material is required to some extent by all fruits, and is 



