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manure, while the rest of the field receives the coarse parts of the 

 manure largely deprived of its valuable constituents. Another disad- 

 vantage of this method is that proper fermentation is interfered with 

 by the leaching out of the nitrogenous matter and the drying action of 

 the wind. The practice of storing manure in large heaps in the field 

 is subject to some extent to the same objections. If, however, the heap 

 is not allowed to lie too long and is carefully covered with earth the 

 loss may be greatly reduced. 



Spreading the manure and allowing it to lie on the surface should be 

 practised only on level fields where there is no danger from surface 

 washing. It has been claimed that when manure is spread broadcast 

 and allowed to lie on the surface there may be a serious loss of ammo- 

 nia into the air, but experiments have shown that, in case of properly 

 prepared manure, loss from this case must be very small. On a leachy 

 soil there may be a loss of soluble constituents in the drainage if the 

 manure is spread a long while before the crop is planted, but in ordinary 

 practice the loss from this source is also likely to be insignificant. In 

 this method of application the fertilising constituents of the manure 

 are uniformly distributed, the liquid portion being gradually and thor- 

 oughly incorporated with the soil particles. One serious disadvantage, 

 however, of the method is that the manure before being ploughed in is 

 leached to a large extent of its soluble nitrogenous compounds, which 

 as we have already observed, are necessary for fermentation; and that 

 for this reason it does not so readily ferment iu the soil. It is highly 

 advisable, therefore, in the case of light or sandy soils, not to follow 

 this practice, but to plough the manure in as soon as spread. 



As to the depth to which it is advisable to plough them. inure in, the 

 general rule should be observed that it should not be so deep as to pre- 

 vent the access of sufficient moisture and air to insure fermentation 

 and nitrification and to permit of rapid washing down of nitrates to 

 the drain. In very compact soils the depth should not exceed 4 inches. 

 Ia light soils this depth may be considerably increased, although in 

 such soils there is more danger of loss by drainage than with heavy 

 clay soils. 



Application in the hill or drill is useful where the supply of manure 

 is limited and the full immediate effect is desired. For forcing truck 

 crops this method is especially valuable. Well-rotted manure is best 

 suited to this method of application. It has been claimed, however, 

 that manure applied in this way sometimes injures the appearance of 

 root crops, especially potatoes, by increasing the amount of scab. 



The so-called parking system, or feeding animals on the land, is a 

 method of application which has many advantages ; but the distribu- 

 tion of the manure by this system is irregular, and if practised in 

 autumn or winter the manure is subject to loss by drainage. 



The application of liquid manure has certain obvious advantages, and 

 is largely practised, especially in Europe. Manure leachings is a quick- 

 acting, forcing manure, and is especially valuable for grass. The 

 expense of cisterns for collecting the leachings and the trouble of haul- 

 ing and distributing, together with the care which must be exercised 

 to prevent loss of nitrogen from the readily fermentable liquid when it 

 stands for any length of time, render it doubtful whether this method 

 is practicable except for special purposes and under peculiar conditions. 



