FARMYARD MANURE 53 



can be thrown on to the manure in dry weather. When 

 the heap is made in the open it should be covered by 

 a layer of earth. The fermentation of farmyard 

 manure may be greatly hindered by mixing with it a 

 small quantity of kainite ; loss of nitrogen is thus pre- 

 vented, but the decomposition of the litter becomes 

 imperfect. 



Well-made rotten manure is a more concentrated 

 plant food than fresh manure, and is much preferred 

 for hght soils, which long manure would leave too 

 open and liable to drought. 



Farmyard manure will contain from 65 — 80 per 

 cent, of water. The nitrogen will usually be about 

 0*45 per cent., but may rise to 0*65 per cent, or higher 

 if produced by highly-fed animals, or with peat moss 

 litter. The ash constituents will be 2-5—3 per cent., 

 exclusive of the sand and earth always present. Of 

 these ash constituents 0*4 — 0*8 will be potash, and 

 0"2 — 0'4 phosphoric acid. One ton of farmyard 

 manure will thus supply 10—15 lbs. of nitrogen, 

 9 — 18 lbs. of potash, and 4 — 9 lbs. of phosphoric 

 acid. 



Farmyard manure is a ^^ general manure'' — that is, 

 it supplies all the essential elements of plant food. 

 The immediate return from an application of farmyard 

 manure is much less than from the same amount of 

 plant food applied in artificial manures. The effect of 

 farmyard manure is spread over a considerable number 

 of years, its nitrogen being chiefly present, not as 

 ammonia, but in the form of carbonaceous compounds, 

 which decompose but slowly in the soil. 



Farmyard manure improves the physical condition 

 of many soils by increasing the proportion of humus 



