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THE BOTANICAL MAGAZINE. 



L Vol. XXI. No. 24; 



Comparison of the stimulating effect of fluorine 

 and manganese. Soil and general manure were the same 

 as in the former experiment. Two pots received 0.002<?£ man- 

 ganese sulphate, (=40 kilo per ha) one further pot 2 milligrams 

 sodium flu oriel and another 20 mg., corresponding to 0.5 and 

 5 kilo Na F per ha, respectively. The stimulants were applied 

 as top dressing in two fractions. (Feb. 20 and March 12). 

 Eight wheat plants were allowed to grow in the pots. Since 

 towards end of April danger from fungi developed, the plants 

 were cut before the ripening of the seeds and weighed in the 

 fresh state with the following result : 





Mn S0 4 



Ni 



iFO.C02g. 



Nj 



1 F0.02g. 



Check 



Total weight, g 



f345 

 1352 





328 





332 



1 / 313 



1 1298 



Weight of ears, g... 



f49 

 150 





47.8 





49.0 



! |48.0 

 (46.5 



This gives the following ratio : 



Average of the 2 Check pots =100 



Manganese sulphate in top dressing at the rate of 40) 



kile per ha J 



Sodium fluoric!, at the rate of 5 kilo per ha =107 



Manganese sulphate had therefore in this case produced a 

 better result than sodium fluoric! ; however this may change on 

 other soils. I} 



1 In certain soils sodium fluorid may le much more quickly transformed into 

 little active calcium fluorid, than in others. 



