234 Report on Crop Production of the 



tion, complete with the exception of potash, the plants grew no 

 better than in pure water. There was no assimilation and no 

 actual growth, because without the action of potash no starch is 

 formed in the chlorophyl bodies. 



Potassium chloride was found to be the best form of potash 

 for buckwheat, the nitrate being next in usefulness. If all the 

 potash is given in form of sulphate or' phosphate, there will 

 develop sooner or later a disease, due to the " passive accumu- 

 lation " of starch; which is not transported so that it may be 

 of use to the plant. 



Sodium and lithium could not replace potash. While the 

 sodium was simply useless for the plant, the lithium in the cell 

 sap had an injurious action on the plant tissues. 



M. Mercadante^ grew oxalis and rumex without potash. The 

 plants did not bear fruit or flowers. The sap contained about one- 

 eighth the free acid found in a normal plant. Besides the oxalic 

 acid the sap also contained tartaric acid, both being in combina- 

 tion with lime. Only small amounts of sugar and starch were 

 found in the sap. 



A. Pagnoul^ reached the conclusion that ash of potatoes, fer- 

 tilized with both soda and potash salts, did not contain even a 

 trace of soda. The roots assimilated the potash but none of the 

 soda. 



M. Georges Ville^ studying the action of salts in quartz sand^ 

 says in regard to potash: ''As soon as this alkali is lacking in 

 the soil, the plant suffers greatly; the stalk, instead of growing 

 vertically, bends as if it wanted solidity. It does not die, how- 

 ever, but the yield scarcely reaches 92 grains." The complete 

 fertilizer gave 337-400 grains. 



'^ From a chemical point of view the closest resemblance exists 

 between potash and soda, ♦ » ♦ but to the plant there is 

 a vast difference, for in the experiment in which the potash was 

 suppressed, and where vegetation suffered so much, the soil was 



*Jahr}>. f. Agr. CJiem., 18 : 257. 



*Comptes rendus, 80:1010, abstracted Jahrb. f. Agr. Chem., 18:25a. 



•Artificial Manures, p. 154. 



