Edible Products. 



76 



[Feb. 1907. 



any investigation on manurial treatment. Hitherto their vise has not been very 

 successful in the Indian districts, (though Phosphoric Acid is very deficient in 

 many of the tea soils), but they have been utilised in large and constantly 

 increasing quantities in Ceylon. They may be applied in three ways, —as an 

 artificial acid phosphate (Superphosphate), as basic slag, or as bones. Bones have 

 beeu omitted, for the moment, but their investigation must certainly come a little 

 later. On the other hand, plots have been laid out (in the same series of experi- 

 ments above indicated for lime; to which are added (1) superphosphate and potash 

 (2) basic slag and potash, (3) superphosphate and potash with nitrogenous manure 

 as nitrate of soda, (4) basic slag and potash likewise with nitrate of soda. 



The manures in which nitrogen and organic matter are the chief valuable 

 constituents remain. We may have nitrogenous manures containing no organic 

 matter like Nitrate of Soda, or Sulphate of Ammonia,— the latter a waste product 

 from gas works. These are usually quick acting, but their effect rapidly disappears. 

 We may, on the other hand, have nitrogenous manures, in which the nitrogen 

 forms part of vegetable or animal matter. Such are the various classes of oilcake, 

 and cattle manure, hitherto the most commonly used materials in the Indian tea 

 districts. In connection with them another question arises. It has been customary 

 to apply the oilcake, for example, at the rate of about 15 maunds per acre once in 

 three years,— or the cattle manure in large quantities at long intervals. Would it 

 not be more effective to add, say, one third the quantity each year, and so give a 

 slight annual stimulus rather than a stronger one at less frequent intervals ? Taking 

 this into account, the complete set of these manurial experiments, as at present 

 laid out, consist of nineteen half -acre plots treated as follows :— 

 Number of Plot 



1 Untreated. 



2 Sulphate of Ammonia, 2 cwts. per acre. 



3 Nitrate of Soda, 2s cwts. per acre. 



4 Superphosphate (3 cwts.) and Sulphate of Potash, (2 cwts.) 



5 Basic Slag (5 cwts.) and Sulphate of Potash, (2 cwts) per acre. 



6 As in 4. with Nitrate of Soda, 2h cwts. per acre. 



7 As in 5, with Nitrate of Soda, 2i cwts. per acre. 



8 Untreated. 



9 Local Oil Cake, 15 maunds per acre, once in three years. 



10 Local Oil Cake, 5 maunds per acre, each year. 



11 Castor Cake (from Calcutta) 15 maunds per acre, once in 



three years. 



12 Castor Cake (from Calcutta) 5 maunds per acre, each year. 



13 Cattle Manure, 20 tons per acre, once in three years. 



14 Cattle Manure, 6| tons per acre, every year. 



15 Lime 15 maunds per acre. 



10 Lime, 15 maunds per acre and local Oil Cake, 15 maunds 

 per acre. 



17 Green Manu ring with mati-kalai, every year. 



18 Green Manuring with mati-kalai, every second year. 



19 Superphosphate (3 cwts) and Sulphate of Potash (2 cwts) and 



Green Manuring with mati-kalai. 



It will be noticed that we have introduced three plots on which the principal 

 manurial treatment used is green manuring with mati-kalai (Phaseolus Mungo) 

 applied annually or at intervals. This is supplementary to a separate series of 

 experiments on various green manures, and will enable us to compare the effect 

 of such dressings (which cost under five rupees per acre) with the much more 

 expensive manures applied. 



