SOILS FEETILIZERS. 



23 



(E. S. R., 31, p. 221) and suggests alterations in the present method of estimat- 

 ing the unexhausted values of manures and of feeding stuffs. The method sug- 

 gested differs from that of Voelcker and Hall in that it distinguishes between 

 digestible and indigestible nitrogen, and it assumes that only half the digestible 

 nitrogen is recovered in the dung heap under good conditions of dung making, 

 that the indigestible nitrogen together with the phosphoric acid and potash of 

 feeding stuffs require four years for exhaustion, and that one-half of the value 

 remaining is exhausted in each season. 



The composition and value of liquid manure, J. Hendkick {North of Scot. 

 Col. Agr. Bui. 19 {1915), pp. 29). — This bulletin reports investigations "under- 

 taken (1) to determine the chemical composition of liquid manure produced 

 under the farming conditions of the northeast of Scotland, and (2) by means 

 of field experiments to determine how far dressings of liquid manure given at 

 various times during the winter under the ordinary conditions of practice will 

 produce increases of crop." 



Analyses of a large number of samples of liquid manure from different farms 

 at each of the three periods during the winter or early spring when liquid 

 manure was being applied showed that individual samples differed greatly from 

 one another and that even the average analyses from different farms differed 

 greatly. The results of analyses of 35 samples are summarized in the following 

 table : 



Composition of liquid manure. 



The manurial constituent present in greatest proportion was potash. Con- 

 siderable nitrogen, nearly all of which was in the form of soluble ammonia com- 

 pounds, was present, but there was on the average more than twice as much 

 potash as nitrogen present. Phosphoric acid and lime were present only in very 

 small amounts. Analyses of fresh urine from feeding bullocks showed that it 

 contained 0.163 per cent of total nitrogen and only 0.012 per cent of ammonia 

 nitrogen. 



In four years' field fertilizer experiments with liquid manure on quarter-acre 

 plats of hay land the liquid manure was applied at different times during the 

 winter, the standard dressing being 2,000 gal. per acre applied in two portions of 

 1,000 gal. each with an interval of a few days between. It was found that a 

 marked increase of hay crop was obtained from the application of liquid manure 

 in winter or early spring. Treatment with liquid manure had no bad effect on 

 clover, but was on the contrary distinctly beneficial in several of the experi- 

 ments. The after effect of treatment with liquid manure was also good. 



While a remunerative return was obtained from an application of 2,000 gal. of 

 liquid manure per acre a correspondingly greater return was not obtained when 

 4,000 gal. per acre were applied. In several cases with the heavier treatment the 

 crop was too heavy and was inclined to lodge. It is concluded that about 2,000 

 gal. of liquid manure per acre for hay land is sufficient and that the profit 

 realized by such an application is sufficient to justify the trouble and expense of 

 applying the liquid manure instead of letting it go to waste. 



15419°— No. 1—16 3 



