GRASS AND THE NATIONAL FOOD SUPPLY 



463 



It is obvious that during some of the summer months there is plenty of 

 grass, and at other times a shortage. 



It is usual to keep as many cattle and sheep on a farm as can eat the grass 

 during the leaner months of the summer. 



In Jersey and Denmark cattle are tethered on the pastures ; when they 

 have grazed the grass around them they are moved off to another spot, and 



Yield of Crude Protein in Grass from 

 cutting durin g the summer nnonbhs . 



1935 



Fertilised 

 (2^iCh<t /Rm 30^ per acre) 



Unfertilised 



2- —\ 



3 



CP 

 < 





o 



2 



' 3 



CP 



< 



a. 



Fig. 



4- 



the pasture is treated with liquid manure. The grass grows again rapidly, 

 and is regrazed when it is 3 or 4 inches high. By this means it is possible 

 to control the grazing, so that the grass never becomes too long and coarse, 

 or matures to seed. 



A more elaborate and more scientific method of controlled grazing was 

 initiated by Prof. Falcke, of Leipzig University, in 1904, in which he used 

 sulphate of ammonia in place of liquid manure . In 1 9 1 6 , Prof. H . Warmbold 

 developed this method in extensive trials at Hohenheim, and about ten 

 years later Mr. T. H. J. Carroll and Sir Frederick Keeble introduced it into 

 England under the name of ' New System of Grassland Management.' 

 In essence, the system consists in dividing a field into six or eight small 

 paddocks, treating the grass with sulphate of ammonia at intervals of a few 



