516 Field Experiments on Root- Crops. 



been regular, and all weighed as mucli as the 200 best, the 

 weight per acre would have been 28 tons ; and had every jard 

 in length been equal to the best yard, the crop would have 

 exceeded 40 tons per acre. 



It follows evidently from these experiments and observations 

 that in considering the efficacy of potash-salts as a manure for 

 swedes, not much reliance can be placed on the increase of 

 30 cwts. of roots per acre, which was obtained from the part 

 of the field manured with these salts, for the condition of the 

 land at the time of sowing swedes had a very much greater 

 influence upon the crop than the manure applied. No manure 

 can compensate for a bad preparation. 



Experimejits %cith Potash-Salts on Potatoes, made at Burcott 

 Lodge Farm in 1866. — The land on which the experiments were 

 tried was dunged in the previous winter. To a portion of the 

 field crude potash-salts were applied on the 28th of February, at 

 the rate of 4 cwts. per acre. The soil was a red sandy loam, 

 Avith a fair admixture of clay, but containing very little lime. 

 On analysis, it yielded the following results : — 



Dried 

 at 212° Fahr 



Organic matter and water of combination .. .. 5' 58 



Oxide of iron 15'74 



Alumina 2*56 



Phosplioric acid '19 



Sulphuric acid '13 



Carbonate of lime "50 



Alcalies and magnesia '95 



Insoluble silicious matter 74*35 



100-00 



The potatoes, York Regents, were planted on the 2nd of April, 

 and were well up by the 25th of May. The crop was dug on 

 September 14th, Produce: without potash-salts, 10 tons per 

 acre ; with 4 cwts. of crude potash-salts, also 10 tons per acre. 



More than one-half of the potatoes were diseased, alike Avhen 

 grown with or without potash. The only difference I could notice 

 was in the somewhat lighter green colour of the potatoe-tops 

 where potash-salts were applied. 



It is but right to state that the field on which the experiments 

 were tried had been dunged two years previously, and had again 

 received a good dressing of rotten dung for this crop ; it there- 

 fore was evidently in too high an agricultural condition to give 

 the potash-salts a fair chance of exerting any beneficial influence 

 upon the potatoe-crop. 



Potatoe Experiments icith Diivcj and Artificials, made in 1866, 

 at Carleton, Carlisle. — The last series of field experiments on 

 which I have to report was carefully carried out by my friend 



