44 



From this we see that barley grown with ammonia salts 

 with superphosphate and alkaline salts (sulphates of potash, 

 soda, and magnesia) was of higher average malting quality 

 than that produced by any other manuring, producing grain 

 of the highest class in eighteen years out of the twenty-four 

 considered, and was distinctly better than nitrate of soda 

 with the same mineral manures. When the alkaline salts 

 were omitted, nitrate gave a better average sample than 

 ammonia salts another instance of the importance of a 

 sufficiency of potash and other similar substances w r hen 

 ammonia salts are used. In both the other applications of 

 the nitrogenous manures that is, by themselves and with 

 alkaline salts the ammonia salts were distinctly better than 

 nitrate of soda in their effect on the quality of the corn. 



The unfavourable influence of nitrate of soda is perhaps 

 due to, or correlated with, its tendency to produce a large 

 proportion of straw, with which is usually found coarseness 

 of the husk enveloping the grain, and a greater proportion 

 of tail corn. Both these points correspond closely with the 

 malting quality as shown in the above table. The follow- 

 ing is the average proportion of grain per 100 of straw, and 

 of tail corn per 100 of total grain, from plots at Rothamsted 

 receiving ammonia salts and nitrate of soda, alone and with 

 mineral manures, for the forty years 1852 to 1891. 



TABLE XXII. 



Grain Tail Corn 



Manures. per 10J per 100 



Straw. Total Grain. 



Ammonia salts, superphosphate, and alkaline salts 85'0 . 3-9 



Nitrate of soda, superphosphate, and alkaline salts 81-4 



Ammonia salts and superphosphate 90-7 



Nitrate of soda and superphosphate 86'0 



Ammonia salts and alkaline salts 88-0 



Nitrate of soda and alkaline salts 81-5 



Ammonia salts 91'2 



Nitrate of soda 86*7 



Average of four plots receiving ammonia salts . . 88-7 

 Average of four plots receiving nitrate of soda . . 83-9 



4-9 

 5-3 

 5-0 

 5-7 

 6-5 

 6-6 

 7-0 



5-4 



5-8 



In each pair of plots the proportion of grain to straw was 

 higher with ammonia salts than with nitrate of soda ; and 

 in each case, except \vhere superphosphate only was added 

 to the nitrogenous manures, the percentage of tail corn was 

 lower with ammonia salts. 



To sum up the matter with regard to barley, sulphate of 

 ammonia gives a large increase in the crop ; and though this 

 is somewhat less on the average than that obtained from 

 nitrate of soda, yet the gain in quality w r ill generally more 

 than make up for the smaller return. On a crop so liable to 

 be injured by over- manuring, the use of sulphate of ammonia 

 for barley after a sheepfold would, of course, almost always 

 be harmful ; but no practical man needs to be told that. 

 After wheat, however, or roots drawn off the land, or under 



