430 



Field-Experiments on Permanent Pasture. 



Plots. Descrit-tiox of Manure. 



3 I 



J 



'i 



5 I 



1 I 

 8 



ol 



10 



Quicklime 



Quicklime 



and 

 Salt .. 



Bone-dust 



Mineral superphosphate 



and 

 Crude potash salts 



No manure . . 



Common salt 



Peruvian giiano 



Crude potash salts 



Mineral guijcrpliosjihatc 



and 

 Peruvian guano 



No manure 



Quantity | 



of Manure, Weight 1 Weight 

 per Plot of Grass per of Grass per 

 of j'^ of an Plot. I Acre. 



Acre. 



bushels. 

 5 



5 



lbs. 



28 



84 

 28 



28 



28 

 28 

 28 

 28 



28 



Increase 



per Acre over 



Average 



Produce of 



Unmanured 



Plots. 



Decrease per 

 Acre. 



cwts. qrs. lbs. tons. cwts. lbs. tons. cwts. lbs. tons. cwts. lbs 



2 15 



14 

 24 



26 

 11 



12 

 16 

 17 

 19 



6 



28 

 56 

 32 



14 72 

 16 108 



The average produce per acre of the two unmanured plots was 

 3 tons 15 cwts. and 40 lbs. 



It appears from the preceding; tabulated results : — 



1. That Peruvian guano produced the largest increase. 



2. The addition of superphosphate to guano had no beneficial 

 effect : on the contrary, it somewhat diminished the produce, for 

 5 cwts. of guano alone produced 6 tons 2 cwts. and 16 lbs. of 

 grass, and the mixture of 5 cwts. of guano and 5 cwts. of super- 

 pho.spliate, only 5 tons 14 cwts. and 72 lbs., or 7^ cwts. less per 

 acre. 5 cwts. of guano appear in this instance to be as much 

 manure as the land could bear at the time of its application, and 

 the addition to the ground of 5 cwts. of a soluble manure like 

 superphosphate probably has placed more soluble matter within 

 the reach of the grass-roots than was conducive to the most 

 luxuriant growth of the grass. 



3. Fertilising materials which are very soluble in water, and 

 are not absorbed chemically and rendered insoluble by the soil, 

 require to be used sparingly, and should always be used in 

 showery weather, in order that they may be washed into a large 

 body of the land. 



The experiments illustrate the force of these remarks un- 

 mistakably. 



