236 MANURES FOR TREES 



humus. Nitrogen is essential for tlie growth and 

 development of all trees. Without nitrogen no 

 growth ; it is as necessary as sunshine and rain ; 

 but the application of nitrogen, in the form of 

 nitrates, etc., must not be overdone or underdone. 

 Economy in fruit and flower growing is essential. 

 To apply the right manures in their proper 

 quantities is the correct way of working. " Usus 

 uni rei deditus et naturam et artem saepe 

 vincit," wrote Cicero nearly two thousand years 

 ago, and the remark is applicable even in these 

 days. 



Sulphate of Ammonia is an indirect bye- 

 product in the manufacture of gas, oven-coke, 

 shale oils and other industries. It is a salt of 

 ammonium and sulphuric acid, and the following 

 is an analysis of a good sample of sulphate of 

 ammonia : — 



Moisture . . . 6 -69 



Sulphate of ammonia. 91 "94 = 19 '5% Nitrogen. 



Impurities . . . 1'47 



Sulphate of ammonia is suitable for all soils 

 except calcareous or chalky lands. It is suitable 

 for clayey and loamy soils, and it increases the 

 sugar in fruits. Sulphate of ammonia is readily 

 absorbed by the roots, and consequently it is 

 quicker in its action than the various organo-nitro- 



