354 SOILS: PROPERTIES AND MANAGEMENT 



This, however, has no significance so far as danger 

 from loss of a soluble fertilizer constituent is concerned, 

 since water, even after a heavy rain, would not pass so 

 quickly through the soil that absorption would not take 

 place, except possibly in the case of soil of a very coarse 

 texture. The depth through which the substance is 

 distributed in the soil may, however, be influenced by 

 the time required for its absorption. Ordinarily ferti- 

 lizers do not penetrate very far into the soil. Demolon 

 and Bronet l have investigated the rate and distance of 

 penetration of certain soluble salts in soils, and find that 

 a total rainfall of ten inches is not sufficient to carry down 

 sodium nitrate in a sandy soil to a depth of eight inches. 



253. Insolubility of certain absorbed substances. — 

 Although bases once absorbed may be easily displaced 

 by other bases, it is difficult to dissolve them from the 

 soil with pure water. Peters 2 treated 100 grams of soil 

 with 250 cubic centimeters of water containing potassium 

 chloride, of which 0.2114 gram of K 2 was absorbed. 

 The soil was then leached with distilled water, using 125 

 cubic centimeters of water daily for ten days. At the 

 end of that time 0.0875 gram of K 2 had been removed, 

 or at the rate of 28,100 parts of water to one part of 

 K 2 dissolved from the soil. Henneberg and Stoh- 

 mann 3 found that it required 10,000 parts of water 



1 Demolon, A., and Bronet, G. Sur la Penetration des 

 Engrais Solubles dans les Sols. Ann. Agron., Tome 28, pp. 

 401-418. 1911. 



2 Peters, E. Ueber die Absorption von Kali durch Acker- 

 erde. Landw. Vers. Stat., Band 2, Seite 113-151. 1860. 



3 Henneberg, W., and Stohmann, F. Ueber das Verhalten 

 der Ackererde gegen Losungen von Ammoniak und Ammoniak- 

 salzen. Jour. f. Landw., Neue Folge, Band 3 (Der ganze Reihe 

 siebenter Jahrgang), Seite 25-47. 1859. 



