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lizer. Bone meal has for many years been successfully used on sugar 

 and coconuts and is recommended as a splendid manure for all estates. 

 It can be shipped direct from home (which is advisable) or obtained in 

 Penang or Calcutta. 



Guano is a well known and valuable manure being the excrement 

 of birds. Many of the limestone caves in Perak and Selangor contain 

 deposits of bat-guano which can generally be collected on payment 

 of a small fee. It is a quick acting and very powerful manure. Its 

 beneficial effect on green crops and grass land is rapid and very 

 maked. Up to the present time I have not heard of it having been 

 used on rubber or coconut plantations but I feel sure that if sufficient 

 quantities can be obtained it will be a valuable manure for these pur- 

 poses. 



Leaf mould is invaluable as a manure either as a mulch round the 

 roots of rubber and coconut trees or when dug into stiff soils. Large 

 quantities of leaves are obtainable on every estate and these when 

 thoroughly decayed form a cheap and most effective manure. 



Many artificial inorganic manures are now in favour. It is true 

 they do not, like stable manure, contain all the food substances re- 

 quired by plants but they contain the most important ones in a more 

 concentrated form. The strength of artificial manures and their adap- 

 tibility for certain crops is determined by their analysis which all res- 

 pectable dealers supply with their goods. All substances entering 

 into plant food must be in a state of fluidity or in the form of gas or air, 

 therefore the chief recommendation of an artificial inorganic manure 

 should be its power of yielding as much soluble matter as possible to 

 the roots and that in a gradual manure. 



Ammonia is one of the chief component parts of all manures and 

 has a powerful stimulating action on the growth of plants. It is sup- 

 plied in inorganic manures chiefly in the form of ammoniacal salts. 



Potassium appears in commerce in the form of potassium sulphate. 

 If the soil is not rich in lime it is advisable when manuring with raw 

 potassium sulphate to add a considerable quantity of quick lime. 



Phosphoric acid is obtainable in various forms. Quickest effects 

 are obtained form superphosphates. If it is necessary to add nitrogen 

 to the soil as well as phosphoric acid a mixture of ammonium sulphate 

 and superphosphates can be used. A well know manure containing 

 those properties is Peru Guano. 



Slag which is a biproduct of iron works contains from forty to 

 sixty per cent phosphate of lime together with silica, oxides of iron, 

 magnesium, sulphur, etc. This is an effective manure for damp 

 soils. In dry soils the action is much less rapid. 



Wood ashes form an excellent manure, being exceptionally rich 

 in potash. The layer of wood ash and charcoal left on a clearing 

 after a burn off is very beneficial to the young crop. Charcoal has the 

 property of absorbing ammonia and other gases and again giving them 

 off as plant food. 



Salt is a useful substance not only as a manure on some soils 

 but for the extermination of slugs, worms, and larvae of different kinds. 



Lime is not naturally found in a free state but in combination with 

 (carbonic) acid forming what is known as carbonate of lime or chalk. 



