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source of lime and phosphoric acid. It is formed by the action of 

 sulphuric acid on hones and various mineral phosphates. Superphos- 

 phate is the base of various fertilizers that are sold for special purposes. 

 A dressing of three or four hundredweight per acre will be useful in 

 orchards that require lime and phosphoric acid. It should be applied 

 annually, and early in spring is the best time to use it. Superphosphate 

 may be applied freely to most soils with advantage. In chalk, or lime 

 soils, however, there is a risk of the soluble phosphate being rendered 

 insoluble, and therefore useless. 



Sulphate of Iron. Most soils contain iron in sufficient quantities for 

 the requirements of plants, but very often this material is not in a 

 sufficiently soluble state, and, therefore, not available. The deficiency 

 may be made good in the shape of sulphate of iron applied in the spring 

 after rain, at the rate of 60 Ibs. per acre. 



Guano. The value of guano depends upon the proportion of ammonia 

 and phosphates contained in the material. These vary considerably, from 

 a high percentage, as in Peruvian, to a comparatively small amount in 

 some kinds from other parts of the world. Guano is somewhat too 

 forcing for fruits, though it may be used with advantage sometimes, and 

 more especially for strawberries. It should be used when growth is 

 active, at the rate of about three hundredweight per acre of Peruvian, 

 and of other kinds larger proportions in accordance with quality. 



Wood Ashes. This is a very useful material, and a good source from 

 which potash is economically obtained. It has also a useful mechanical 

 action on heavy soils. 



Gypsum (Sulphate of Lime). This material occurs naturally in many 

 parts of Australia, and where it can be got cheaply may be turned to 

 good account as a fertilizer. It is not required in soils that are freely 

 supplied with lime, but is a good dressing for heavy clay, alluvial, or 

 peaty land. Fruit trees and vines will often derive great benefit from 

 this material, which should be applied annually at the rate of about 

 half-a-ton per acre. 



Salt (Chloride of Sodium). This material may be used to a moderate 

 extent in land that is deficient in saline matter, and will also prove 

 useful in helping to keep down slugs and other pests. 



Soda is a special requirement for the Strawberry, Apple and Fig, and 

 to an important though lesser extent by the Pear, Orange, Lemon and 

 Quince. It may be applied in the form of nitrate of soda. 



Compound Fertilizers. By mixing special fertilizers, according to the 

 particular requirements of the different fruits, cultivators are enabled 

 to manure their orchards to the best advantage. As a matter of course 

 the proportions must vary, but the particular material that will supply 

 the leading want must be dominant. 



To Ascertain the Special Requirements of the Land. This is not 

 always an easy matter for the cultivator, and even if he can afford the 

 cost of an analysis, the report of the chemist, as explained before, is not 

 altogether reliable. To a fairly satisfactory extent, however, the desired 

 information may be gained by trials of crops between the trees. Rye 

 absorbs potash and phosphoric acid in large quantities. Potatoes must 



