43 



The results for the phosphoric acid in the ash analyses would seem 

 to contradict the theory of Crochetelle/ that the carbonate of Ume 

 injures the plant by decreasing the assimilation of phosphoric acid. 

 The experimeiits of Priainshnikow ^ with different phosphates also 

 contradict Crochetelle's assumption, as the availabihty of phosphoric 

 acid in mono and dicalcium phosphate, Thomas slag, and iron and 

 aluminimi phosphates was not depressed by carbonate of hme, 

 although the availabihty of phosphoric acid in bone meal and trical- 

 cium phosphate was depressed. 



When the results reported here are compared with the results 

 obtained by Fhche and Grandeau with certain trees,' strildng simi- 

 larity in some respects is apparent. The bean tree, which was imaf- 

 fected in growth by the carbonate of hme, was unaffected in its ash 

 com230sition except for a depression in the magnesia. Tlie maritime 

 pine and chestnut, whose gi-owths were strongly depressed on the 

 calcareous soils, showed a marked increase in hme and a marked de- 

 crease in iron and potash in the ash, when grown on the calcareous 

 soils. All these trees contained a greater percentage of ash in the 

 dry matter when grown on the calcareous soUs than wh6n grown on 

 the noncalcareous soil. The above results differ from those obtained 

 by us in that a strong depression of potash was noted in the pine and 

 chestnut on the calcareous soils. 



The view that the injury to plants grown on calcareous soils does 

 not he simply in increasing the hme in the plant seems to bo borne 

 out by the chrect experiments with pmeapples and by experiments in 

 progress with rice. It is also the conclusion arrived at by Fhche and 

 Grandeau, and the opinion of Euler that " * * * ^j^j. gchafj. 

 Uche Einfluss des Kalkbodens ein in chemischer Hinsicht indirekter 

 ist."* Jost^ is of a similar opinion. Euler and Jost, however, 

 beheve that the indirect action of the lime m injuring the plants hes 

 in depressing the absorption of potash, apparently basmg their 

 opinion on the analyses of Fhche and Grandeau. From the results 

 reported here it appears that the incUrect action of the hme hes more 

 in affecting the iron absorption than in depressing the potash; since 

 when potash fertihzers are hberally used there is a depression in 

 growth, but no depression in the amount of potash absorbed. 



It should be borne in mind that the results reported here do not 

 warrant a decisive conclusion that the diminished growth of all those 



' Crochetelle, J., Ann. Sci. Agron., 2. ser., 8 (1902-.3), II, p. 43. 



> Prianishnikow, D., Landw. Vers. Stat., 75 (1911), Nos. 5-6, p. 357. 



' See p. 8. 



* Euler, II. Grundlagan und Ergebnisse der Pflanzcnchemie. Braunschweig, 1909, pt. 3, p. 153. 



6 Jost, L. Vorlesungen iiber Pflanzenphysiologie. Jena, 1908, 2. ed., p. 111. 



