238 FARMYARD MANURE [CHAP. 



roots are to be taken in the following spring. Even 

 on the lightest soils the land will be more benefited 

 thus, than if the manure is made up into a mixen and 

 only put on immediately before the roots are grown. 

 Sometimes, of course, a potato grower must have a 

 supply of well-rotted manure to put in the drills 

 immediately before planting ; this can often be got 

 from the lower layers of the earliest used boxes or 

 yards, since a mixen should be avoided as much as 

 possible. The principle to keep in mind is that every 

 disturbance of farmyard manure results in loss, and that 

 the shorter the time which elapses between the dropping 

 of the dung and its application to the land, the less this 

 loss of fertilising material will become. 



In considering the value of farmyard manure as a 

 fertiliser, one has to keep in mind that it is an essential 

 product of the farm, and that it must constitute the 

 main source of manure for the land under the conditions 

 of ordinary mixed farming, where artificial manures will 

 only be used as supplements and not as rivals. It is 

 only in certain special cases, such as potato or hop 

 growing, where the ordinary course of farming does not 

 supply as much farmyard manure as is wanted, that the 

 question has to be decided whether artificial manures or 

 dung from the towns shall be purchased, or again, 

 whether stock shall be fattened solely with the view ot 

 making manure. 



As a fertiliser, the chief value of farmyard manure 

 lies in the fact that it contains all the elements of a 

 plant's nutrition — nitrogen, phosphoric acid, and potash 

 — though for a well-balanced manure the phosphoric 

 acid is comparatively deficient. Moreover, the nitrogen 

 is present in various forms of combination, varying from 

 the rapidly acting ammonia compounds, down to some 

 of the undigested residues which will remain for a very 



