No. 2, September, 1920] SOIL SCIENCE 297 



tion, if it is negative, potassium is lacking. — The plants ^rom the plats without fertilizer 

 and with full fertilizer usually contain the same percentages of N and PjOj. Only the potas- 

 sium content of the straw is higher in the fully fertilized plot than in the unfertilized plot. 

 A comparison of the plant analysis of unfertilized and fully fertilized plots gives no informa- 

 tion as to the plant food in a soil. The fertilizer requirement of a soil becomes evident if the 

 plants of two incompletely fertilized plots arc investigated, e.g., plots receiving (1) N, and 

 (2) PjOs-f-KvO applications of fertilizer. If thereupon the ratio of N:K 2 is less than 100:200 

 potassium is lacking; if it is wider, then sufficient potassium is present. If the ratio N : P 2 0& 

 from the nitrogen plot is wider than 100:3.5 it lacks in phosphoric acid; if less, then no lack 

 exists. If from the P 2 6 +K 2 0-plot the ratio of N : P 2 6 is less than 100:60 it lacks in nitrogen. 

 If the ratio of Si0 2 : N is wider than 100 : 6 there is not sufficient N present ; if less, the N content 

 is sufficient for wheat growth. If the N percentage in the wheat straw found for the N-plot 

 is considered as 100, then enough N is present in the soil of the P 3 06-r-K.20-plot when the ratio 

 of the 2 percentages is less than 100:60. — C. E. Leighty. 



2276. Reimer, F. C, and H. V. Tartar. Sulfur as a fertilizer for alfalfa in Southern 

 Oregon. Oregon Agric. Exp. Sta. Bull. 163. 40 p. 9 fig. 1919. — Various fertilizers contain- 

 ing sulfur, such as flowers of sulfur, superphosphate, gypsum, iron sulfate, ammonium sulfate, 

 potassium sulfate, magnesium sulfate and sodium sulfate, on various types of soil generally 

 increased the yields of clover and alfalfa very greatly. Most of the soils experimented with 

 were well supplied with potassium, calcium, magnesium, and iron but contained only limited 

 amoimts of sulfur. None of them were acid, and none contained noticeable amounts of alkali. 

 Analyses of the alfalfa plants which had received applications of sulfate fertilizers showed 

 that they had larger root systems with more nodules on them and that they contained much 

 more sulfur, more protein, and more nitrogen. In the hay from the sulfur fertilized plats 

 from 71 to 79 per cent of the sulfur was in the organic form, the remainder in the sulfate form, 

 while from the unfertilized plats it was all in the organic form. Up to the present time the 

 returns from the use of superphosphate have not been greater than those from calcium sulfate 

 alone. Flowers of sulfur produce as marked results as does calcium sulfate but a somewhat 

 longer period is required since it must first be changed to the sulfate form before it can be 

 utilized by the plants. On soils deficient in lime, flowers of sulfur should be used only in con- 

 junction with liberal quantities of lime or rock phosphate to avoid conditions of acidity. — 

 E. J. Kraus. 



SOIL BIOLOGY 



2277. Bornebusch, C. H. Bed0mmelse om Skovjordens Godhed ved Hjaelp af Bund- 

 floraen. [Judging the quality of soil by the flora.] Dansk Skovforenings Tidsskr. 5: 37-50. 

 1920. 



2278. Fellers, C. R., and F. E. Allison. The protozoan fauna of the soils of New Jersey. 

 Soil Sci. 9: 1-25. PI. 1~4- 1920. — Protozoa were found in all soils examined, the number of 

 species ranging from 2 to 28. About 5000 per gram of soil were found. It is believed that in 

 normal New Jersey soils, the protozoa exist mainly in a nontrophic state. — W. J. Robbins. 



2279. Geilmann, [— ]. Untersuchung des Bakteriennahrpraparates der Superphosphat- 

 fabrik Nordenham. [Investigation of the bacterial food preparation of the Nordenham super- 

 phosphate factory.] Jour. Landw. 67: 209-227. 1919. — The superphosphate factory at Nor- 

 denham has introduced a peat preparation which is designed to furnish food material to soil 

 bacteria and to stimulate them to greater activity. The preparation itself is not supposed 

 to act as a fertilizer, but only to bring about nitrogenous fertilization through increased bac- 

 terial activity. Better physical condition and higher productive power of the soil and pre- 

 vention of lodging of grain crops should then result. These investigations have shown: (1) 

 the absolute ineffectiveness of the preparation; (2) that an increase in nitrogen content of 

 the soil does not result from use of the preparation; (3) that it does not act in the least as 

 uitrogenous fertilizer; and (4) that it does not result in increased bacterial activity either in 

 the soil or in nutrient solutions, but that any good results are due to the CaCOj content. — 

 C. E. Leighty. 



