28 MAXURES 



Town-sweepings sometimes form a useful manure. Though 

 iu some cases they consist largely of sand, in others they contain 

 large quantities of organic matter. The refuse from the neighbour- 

 hood of markets are especially useful as a manure, while scrapings 

 from side-drains often contain a large amount of humus and other 

 manurial substances ; their liability to contain troublesome weeds 

 is, however, an objection to their use on field crops. 



Coir-dust. This decomposes so slowly that it can hardly be 

 said to be of much value as a fertiliser. It has, however, a bene- 

 ficial mechanical effect on certain soils, especially such as are 

 deficient in humus. It may with advantage be used to give " body" 

 to potting soils, but it should always be well leached in the open 

 air and rain before use. In the neighbourhood of Colombo and 

 coast towns generally, this is largely employed for pot plants. 



Woollen refuse and shoddy. These are waste materials from 

 woollen and cloth mills, and are used in Europe to some 

 extent in the manufacture of manures. It is said that they usually 

 contain from 5 to 10 per cent, of nitrogen, and that their manurial 

 effects extend over two or three years. The more finely divided 

 the material the more readily it decomposes in the soil, and the 

 more evenly it can be distributed. This form of manure is com- 

 monly used in the cultivation of Hops in England. 



INORGANIC MANURES 



Lime. Lime is a necessary element of the food of plants, 

 enters into the composition of every form of vegetable life, and few 

 soils that do not contain it in some form. But as a manure in 

 itself, lime rarely needs to be added to the soil ; as an indirect 

 fertilising agent, however, it is of the greatest importance. It 

 being necessary for all organic or vegetable matter in the soil to 

 undergo decomposition before the contained elements are rendered 

 available for use as plant-food, lime in its hot or caustic condition 

 is one of the most powerful agents for effecting such decomposi- 

 tion. Thus an application of lime to "acid" or "sour" land, 

 often has most beneficial results ; whilst its action on heavy or 

 inert soils is an important aid to fertility, causing the soil to become 

 friable, and thereby giving free access to air and water, which 

 encourage the growth of soil bacteria. It is considered that any 

 soil containing less than ^ per cent, of lime cannot be brought to a 

 high state of fertility. Lime is valuable for pasture land, as well 

 as for field and garden crops, whilst its effect as a preventive 

 against fungoid diseases (e.g., club-root) and insects in the soil is 



