632 EXPERIMENT STATION BECOED. 



and Kravkov (E. S. R., 12, p. 620) in showing that the unfertihzed soil lost water 

 most i-apidly, while the soil fertilized with potash and nitrogen gave off water most 

 slowly, and phosphoric acid generally only slightly retarded evaporation. In the 

 field experiments a large number of determinations were made, not only of the 

 moisture, but of the temperature of the differently fertilized plats which were seeded 

 to spring wheat. The results show that the application of nitrogen resulted in a 

 larger yield and left the soil exhausted to a greater extent of water than the other 

 fertilizers. The deficiency of water under ordinary conditions persisted for a long 

 time. The other fertilizers were apparently without marked effect upon the water 

 content of the soil. The direct influence of the fertilizing on the temperature was 

 apparently of no practical importance. 



On nitrate fermentation and its importance in relation to the biological 

 processes of the soil, J. Stoklasa {-Deut. Landw. Presse, 28 {1901), Nos. 79, pp. 

 666, 667; SI, pp. 683, 684). — This is a continuation of investigations on denitrification 

 in Avhich the author has attempted to determine (1) the source of carbon most favor- 

 able to the denitrifying organisms in the culture media, (2) the nature of the chemical 

 changes which take place, and (3) the importance of denitrification in relation to the 

 soil processes. The results of the first two lines of investigation have been reported 

 elsewhere (E. S. R., 12, pp. 37, 614), and are only briefly reviewed in this article. 

 The author concludes that there are present in soils and in manures two principal 

 groups of bacteria which cause denitrification. The first group contains Bacterium 

 hartlebii, B. fluorescens liquefaciens, B. pyocyaneum, B. stutzeri, B. ceniropimctatum, B. 

 aiefacienH, B. denitrificans {B denitrificans and B. coll commune), B. nitrovorum, etc. 

 The characteristic of these organisms is that they reduce nitrates to elementary 

 nitrogen. The second group contains B. megatherium, B. mycoides, B. subtilis, B. 

 mesentericus vulgatus, B. ramosus, B. typhi abdomiiialk, B. coli communU, Proteus vulgaris 

 and P. zenkeri, B. radicicola, Clostridium gelatinosum, etc. These organisms as a rule 

 simply reduce nitrates to ammonia without the formation of elementary nitrogen. 

 They also appear to have the power of assimilating the ammonia so formed. This 

 is especially true of B. radicicola which is found in the tubercles of leguminous plants 

 and of the alinit bacteria. The nitrogen set free during the process of denitrification 

 appears to be more active than that of normal air and is more readily assimilated 

 by the organisms of the soil. 



Pot experiments on the influence of rapid and complete drying of the soil 

 on the growth of sugar beets, J. Vanha {Oesterr.-Ungar. Ztschr. Zuckerind. u. 

 Landw., 30 {1001), p. 146; ahs. in Centbl. Agr. Chem., 30 {1901), No 11, p. 787).— In 

 connection with experiments in drying the soil to destroy injurious organisms, the 

 author observed the effect of this treatment on the growth and yield of the beets. 

 It was found that neither the total yield nor the quality of the beets was injuriously 

 affected by the drying of the soil. 



Is the chemical analysis of soils necessary to determine their fertilizer 

 requirements? {Dettt. Landw. Presse, 28 {1901), No. 93, p. 778). — An argument 

 to show that chemical analysis is not necessary for this purpose, and is seldom, and 

 only in exceptional cases, a reliable guide to the fertilizer requirements of soils. 



The composition of soils as shown by the plant, C. Schreiber {La composition 

 denos sols reviin' par la }>lante. Brussels: Louis Vogels, 1901, pp. 52, figs. 19). - 



A contribution to the knowledge of marsh soils, J. Steuve {Filhling's Landw. 

 Ztg., 50 {1901), Nos. 21, pp. 758-765; 22, pp. 784-786).— This is a discussion of the 

 physical and chemical character of different classes of marsh soils found in Ger- 

 many. The close relation between the productiveness and the proportion of clay 

 and other fine soil particles is pointed out. For the heavier soils marling is stated 

 to be the most effective means of improvement. 



Soils, T. S. Dymond and F. Hughes {Notes on agricultural analyses. Chrhii.^ford: 

 County Technical Laboratories, Essex Technical Listruction Committee, 1901, pp. 5-11). — 



