290 Farmyard Manure. 



One-half of this, say 12 lb., will reappear as manure, and to 

 this has to be added the whole of the dry matter in the litter, 

 say 10 lb., making the daily output of dry matter in farmyard 

 manure 22 lb. Needless to say, it may be much more or much 

 less, depending on the age and size of the animals, and on the way 

 in which they are fed and littered. Ordinary farmyard manure 

 is, of course, not dry ; on the contrary, it contains about 75 per 

 cent, of water. The daily output will therefore weigh not 22 lb. 

 but 88 lb., say J cwt. Thus on a six months' keep the amount of 

 farmyard manure yielded will be about 6\ tons. This calculation 

 applies to full-grown cattle ; if the stock consists, as it generally 

 does, of a fair proportion of younger animals, the output per head 

 may be only 3 or 4 tons. It follows that on a farm with a 

 mixed stock of 50 head, comprising 3 or 4 horses, enough dung 

 should be produced during winter to give a dressing of 10 or 

 12 tons per acre to about 15 — 20 acres of land, or 3 — 4 acres 

 less when allowance is made for loss during storage. 



From the manurial point of view the three substances that are 

 of most importance in the food are nitrogen, phosphoric acid, and 

 potash. Although only one-half of the solid matter in the food 

 reappears in the manure, at least three-quarters of the nitrogen, 

 and nine-tenths of the phosphoric acid and potash, are voided. 

 These proportions will be considerably reduced in the case of 

 very young animals, and increased in the case of fattening 

 cattle. Of the nitrogen that passes through an animal a larger 

 proportion finds its way out in the urine than in the solid excreta. 

 The same is true of the potash, whereas the phosphoric acid — 

 i.e., the phosphates — are chiefly voided in the dung. It will thus 

 be seen that two of the three valuable elements of plant-food are 

 more abundant in the liquids than in the solids of animal excreta, 

 and, not only so, but, pound for pound, the substances in the 

 liquids are much more valuable for crops because they are much 

 more readily available. The Rothamsted experiments have 

 shown that much of the nitrogen in the solid part of dung can 

 hardly be said to be of any use to plants, whereas the nitrogen of 

 the liquid portion is almost as active and therefore as valuable 

 as nitrate of soda or sulphate of ammonia. 



In a ton of ordinary farmyard manure there is as much 

 nitrogen, phosphate, and potash as in twelve or fifteen shillings' 



