SOILS FERTILIZERS. 321 



of plant food in the soil. His general conclusion is in harmony with conclu- 

 sions from previous work at the same place, namely, that it is necessary to 

 (leal with composites of a large number of samples of soil carefully taken over 

 the area of the plat, about one sample for each square meter being necessary. 



The importance of a knowledge of the soil to colonial agriculture, P. 

 Vagelek (Tropcnpjkinzer, 1// {1910), No. 10, pp. 521-527). — The importance of a 

 knowledge of the soil to the pioneer farmer is pointed out. 



The conservation of the fertility of the soil, A. D. Hall and E. J. Russell 

 (Rpt. Brit. Assoc. Adv. Sci., 1909, pp. 710-713). — This article covers practically 

 the same ground as an article already noted (E. S. R., 23, p. 519). 



Agricultural practice in the Indies, H. Van Warmelo (Cultura, 22 {1910), 

 Nos. 262, pp. 317-329; 263, pp. 372-377; 26Ji-265, pp. 437-////8).— This is a dis- 

 cussion of factors affecting the fertility of the soil, such as composition, soil 

 flora and fauna, depth of surface soil, physical properties, and climatic condi- 

 tions, which are beyond the control of man, and soil cultivation and improve- 

 ment which are more or less within his control. The discussion applies par- 

 ticularly to conditions such as prevail in the Dutch Bast Indian possessions. 



Soil robbery and fertilizing in the light of recent experiments; Schneide- 

 wiND {Landio. Wchnschr. Sachscn, 12 {1910), No. 12, p. 93; ahs. in Cheni. Ztg., 

 S.'i {1910), No, 62, Repert., p. 2-^1). — Experiments which have been carried on 

 for a number of years by the author indicate that under ordinary methods of 

 intensive culture with liberal use of manure and fertilizers there was a marked 

 depletion of the nitrogen and potash supply of the soil. There was a relative 

 increase of the phosphoric acid under such a system. 



Different kinds of stable manure as sources of phosphoric acid, M. A. 

 Egorov {Zhitr. Opijtn. Ayron. {Russ. Jour. Expt. Landw.), 11 {1910), No. 2, 

 pp. 178-186, fig. 1). — Comparative tests were made of monopotassium phosphate, 

 phytin, iron phosphate, mouocalcium phosphate, and pigeon, cow, and horse 

 manure in pot experiments with pure sand (8.S lbs. per pot), the crop grown 

 being oats. A basal fertilizer mixture of calcium nitrate, magnesium sulphate, 

 potassium chlorid, and ferric chlorid was used, and the different materials 

 named above were used in amounts furnishing 0.2S3S gm. of phosphoric acid 

 per pot. 



It was found that in general the phosphoric acid of phytin was well assimi- 

 lated by the oats. The phosphoric acid of the different kinds of manure was 

 more assimilable than that of the normal culture solution. The amount of 

 phosphoric acid assimilated was greatest in the case of horse manure, and this 

 is in agreement with the results of analyses, which showed the largest amount 

 of easily soluble phosphoric acid in this material. 



The author is of the opinion that while the results of these experiments do 

 not warrant generalizations they show that it is important to take into account 

 not only the total phosphoric acid, but also the forms in which it occurs in 

 manures. 



The manurial value of different legumes, R. W. Thatcher {Washington 

 8ta. Popular Bui. 32, pp. //). — This publication reports the percentage of nitro- 

 gen in tops, roots, nodules, and whole plant of a number of legumes grown on 

 the college farm in 1909, and discusses the needs of the soil of different parts 

 of the State with reference to growth of legumes for green manure. The nitro- 

 gen in dry matter of the whole plant varied from 1.5 per cent in alfalfa to 3.5 

 per cent in Tangier pea {Latliyrus tingitanus), and that of nodules from 1.6 per 

 cent in case of sanfoin to 6.92 per cent in case of alfalfa. 



The action of ammonium sulphate and sodium nitrate, Lindenberg {Ilhis. 

 Landw. Ztg., 30 {1910), Nos. 81, pp. 757, 758; 82, pp. 768, 769).— A resume of 

 the results of various experiments shows that the relative efficiency of 100 per 



