SOILS FEETILIZERS. 125 



« 



p. 538), who observed a favorable influence of ammonium nitrate on the assimi- 

 lation of phosphoric acid from difficultly soluble phosphates. In 2 tests, with 

 the entire root system in the solution, ammonium nitrate gave a weakly alkaline 

 reaction. Potassium nitrate was generally physiologically alkaline, but weaker 

 than sodium nitrate. Calcium nitrate was physiologically alkaline. Ammonium 

 chlorid was decidedly acid, and very injurious to the roots. Solutions of potas- 

 sium, sodium, magnesium, and calcium chlorids and sulphates were weakly 

 alkaline. 



The general conclusion drawn from these studies is that the change in the 

 reaction of the solutions was not determined solely by. the process of assimila- 

 tion of one or of the other ion by the plant roots, but that there was an exosmose 

 of calcium and potassium (and probably other elements) from the root cells. 

 This phenomenon of exosmose is regarded as the probable e«:planation of the 

 toxicity of the solutions of pure salts and makes intelligible the action of cal- 

 cium salts in lessening the toxicity of pure salt solutions. 



Influence of phosphatic and potassic fertilizers on the chemical compo- 

 sition of the forage of natural pastures, P. Ciiavan (Anu. Affr. Suisse, 12 

 {1011), 'So. li, pp. 2.59-272, figs. 3). — ^.Vnalyses of grasses, legumes, and other 

 plants growing on Alpine grass lands near S^chey, Switzerland, are reported, 

 showing that fertilizing with phos])hates increased the cellulose content of the 

 plants ;is a result of the influence of the phosphoric acid in hastening maturity. 

 Fertilizing with phosphates and potassic fertilizers increased the phosphoric 

 acid and potash content of the ash of the plants. The use of both fertilizers, 

 but particularly the phosphatic fertilizer, promoted the absori^tion of nitrogen 

 from the soil by Graminese and other families of plants. They also increased 

 the fertilizing eft'ect of the organic matter of the soil. Phosphatic fertilizers 

 increased the potash content of the plants. These results differ materially from 

 those reported by A. Stutzer, who found that phosphatic fertilizers had little 

 effect upon the yield of Graminese, increased but slightly their content of 

 phosphoric acid, and did not increase the potash and nitrogen content of the 

 plants. 



The after effect of fertilizing with various potash rocks on moor soils, 

 II. VON Feilitzen (Dent. Landw. Prcsse, 39 (1!)12), Ao. 21, p. 250, fig. 1).—A 

 brief account is here given of comparisons of phonolite, nephalin, and similar 

 substances with potash salts. These showed that there was an appreciable 

 after-effect of both the phonolite and the nephalin, but that during the second 

 year as well as the first the increase did not compare with that obtained with the 

 water-soluble Stassfurt salt. 



Experiments on the action of kainit, 40 per cent potash salt, and phono- 

 lite, 1904-1910, W. ScHNEiDEWiND, D. Meyee, and F. Muntee (Ai-b. Deut. 

 Landw. GeseJl, 1911, Xo. 193, pp. 113; ahs. in Zentbh Agr. Clicm., J^l (1912), 

 No. 3, -p/x 165-110). — This is a detailed account of pot experiments on (1) 

 absorption of potassium and sodium salts in fall and spring fertilizing, (2) the 

 action of sodium chlorid and sulphate and magnesium chlorid and sulphate on 

 fodder beets, (3) the action of increasing amounts of sodium and magnesium 

 chlorids and magnesium sulphate on plant growth, and (4) the action of phono- 

 lite and Pohl zeolite fertilizer (lime trass) in comparison with potassium 

 chlorid and carbonate ; and field experiments comparing the potash fertilizers 

 named on potatoes, sugar beets, fodder beets, wheat, rye, and bai'ley. 



Among the more important general conclusions arrived at from these experi- 

 ments were that spring application of potash fertilizers gave decidedly better 

 results than fall application on sandy soils in case of pots which had not been 

 freshly filled in the fall. This is ascribed to the washing out of potash from the 

 soil with fall application. Spring applications were better in all cases with 



