SOILS FETtTTTJZETtS. 821 



iiiiiy be uiurc iiiiporlanr than the varying properties of tlie phosphates. Lupines, 

 lor example, can .show, with an apatite lilce i)hosphorite, a considerable devel- 

 opment not inferior to that witli amorphous i)hosphorites, while the Gramineaj 

 give with any phosphorite an extremely poor yield. In field cultures, however, 

 the influence of the soil seems to predominate over everything else. 



(5) Iron and aluminum jihosphatc's are not to ])e considered as unavailable 

 to the plants. 



(6) As Votchal has also shown, potash mica proved in these experiments to 

 be a considerably better source of potash than orthoclase. 



(7) The data of the sand and water culture experiments regarding the im- 

 portance of chlorin for plants do not corroborate the generally accepted opinion 

 of the usefulness of chlorin as such for plant life. Of more importance, prob- 

 ably, is its influence on the physiological reaction of the culture media. 



(8) The liming experiments lead to the following conclusion: While it is 

 true that the oi)timum amount of lime introduced depends not only on the prop- 

 erties of the .soil, but also on those of the plant, it seems to be beyond a doubt 

 that the influence of the soil is much stronger than that of the i)lant ; thus the 

 lupine, which is considered a calcifugous plant, tolerated on a chernozem soil 

 larger iiuantities of lime (1 per cent of the total weight of the soil) than oats 

 on a marshy clay. — p. fireman. 



On the value of soil analyses for ascertaining the fertilizer requirements 

 of soils, M. Weibull (Malmd. Ldits K. H iishdll. .Sdllsh: Kvrili^-^hr., 190.j, No. 3, pp. 

 o!)2-597). — The article gives a brief summary of the author's views with regard 

 to the practical value of soil analysis, based largely on the experience gained 

 (luring several years' field experimentation on Swedish farms, in connection 

 with chemical and mechanical analyses of the soils on which crops were grown. 

 He concludes that determinations of the nitrogen and phosphoric-acid contents 

 of a soil are of no practical value, since all normal soils respond to nitrogenous 

 fertilization, irrespective of their nitrogen content, and no definite relation has 

 been found between the phosphoric-acid content of the soil and the manner in 

 which they respond to applications of this ingredient. As regards potash, three 

 points should be kept in view, the potash content of the soil, its stiffness (con- 

 tent of clay), and the crop to be grown thereon. If a soil contains less than 

 the following average percentages of potash .soluble in warm hydrochloric 

 acid (sp. gr. 1.1), it is nearly always benefited by potash fertilizers: Heavy, 

 medium, and light clay soils, 0.25, 0.20, and 0.15 per cent, respectively: clayey 

 sandy and sandy soils, 0.12 per cent. Potatoes, barley, and other crops which 

 need considerable soluble potash call for potash fertilizers when grown on a 

 soil containing as nuich as or less potash than given; on the other hand, oats 

 under similar conditions will not require potash. 



As regards lime, the reaction of the soil is important. Acid soils always 

 require applications of lime, at least suflicient to change their reaction to 

 neutral. Neutral soils as a rule only need lime when their content of assimi- 

 lable lime is less than 0.25 per cent, or in the case of heavy clay soils, where 

 an addition of quicklime or slaked lime will decrease their stiffness. Alkaline 

 soils do not, generally speaking, need lime, but if very heavy may be imi)roved 

 physically by applications of burnt or slaked lime, — f, w. woix, 



A contribution to practical soil analysis, M. Weibull (Chem. Ztg., 30 

 {1906), So. .7.0. p. 7,22: nhs. hi Chew. CeiithL. 1906. 77, No. 8, p. 103). — See 

 abstract above. 



The relation of sodium to potassium in soil and solution cultures, .1. F. 

 Bre.vzeale {Jour. Aincr. Chem. Soc, 28 {1906), No. 8, pp. 1013-1025, pi. 1).— 

 This subject was studied in a series of experiments with wheat and one ex- 



