Scientific Agriculture. 



274 



(March, 1909. 



Phosphoric acid is obtainable in 

 various forms. Quickest effects are ob- 

 tained from superphosphates. If it is 

 necessary to add nitrogen to the soil as 

 well as phosphoric acid, a mixture of 

 ammonium sulphate and superphos- 

 phates can be used. A well-known man- 

 ure containing those properties is Peru 

 Guano. 



Slag, which is a byproduct 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 bene- 

 ficial to the young crop. Chaccoal 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 exter- 

 mination 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 car- 

 bonate of lime or chalk. 



Quick lime is formed by driving off the 

 carbonic acid by burning. It is ex- 

 tremely caustic and quickly decomposes 

 vegetable and animal matter, hence its 

 value as a fertiliser for soils containing 

 large quantities of peat, consisting of 

 roots and fibres, that would otherwise 

 remain a long time in an undecomposed 

 state. Caution is necessary in applying 



lime to some soils as it possesses the 

 property of setting free ammonia, one of 

 the indispensable constituents of plant- 

 food. Lime is also a valuable fungicide. 



In this country plant-food substances 

 are easiest obtainable in combination in 

 the form of one of the many artificial 

 manures now on the market which are 

 composed in such a manner as to contain 

 as near as possible in a concentrated 

 form the quantities of each substance 

 necessary for the healthy development 

 of plants. 



When ordering manures it is always 

 advisable to order direct from home 

 from some firm of good repute. 



The present prices of these manures 

 may stand in the way of their being 

 generally used, but it is reasonable to 

 suppose that, if a demand arose, ship- 

 ments could be made from home at 

 reasonable i*ates. 



The good effects of manures on coco- 

 nuts is indisputable, and from what we 

 at present know the yield of latex from 

 para rubber trees is considerably in- 

 creased by their application, and it is 

 possible that the quality is also im- 

 proved, but this, I think, is an open 

 question at the present moment. At 

 any rate further results of experiments 

 will be waited for with interest in order 

 to find out whether the rubber is equal 

 in quality or better than that from 

 unmanured trees, and whether the extra 

 yield will justify the extra outlay. I 

 don't know that these points have b?en 

 demonstrated up to the present time, 

 but everything points to such being 

 the case. — Agricultural Bulletin of the 

 Straits and F. M. States, Vol. VII., No 

 12, December, 1908. 



