924 EXPERIMENT STATION RECORD. 



example, a crop of winter wheat or rye takes up from 71.25 to 97.97 lbs. of 

 nitrogen per acre, while, according to results obtained in these observations, 

 from 75.71 to 100.65 lbs. of nitric nitrogen are produced in the soil to depths 

 of from 20 to 40 cm. 



An experiment on further improvement of pure culture inoculation 

 methods for leg'uminous plants, K. StOrmer {Mitt. Landw. Inst. Leipzig, 

 1901, A'o. S, PI). 113-126, /iff. 1). — The article briefly reviews the present status 

 of inoculation methods, pointing out the fact that the main object now to be 

 attained is to increase the virulence of the tubercle bacteria. In order to accom- 

 plish this it is necessary to protect the bacteria from the injurious effect of 

 excretions from the germinating seeds on which the cultures are used, and to 

 secure cultures which during germination of the seed will produce strong infec- 

 tion in the soil in the vicinity of the roots of the plant. 



The author reports experiments on soy beans in which the tubercle bacteria 

 were grown in various media and protected from the injurious effect of the 

 excretions of the germinating seed by applications of powdered calcium car- 

 bonate and gypsum to the seeds while still moistened with the culture solution. 

 It was found that the addition of milk alone to the tubercle cultures was not 

 sufficient to prevent injury. Better results were obtained with cultures con- 

 taining peptone and grape sugar. The use of lime and gypsum greatly increased 

 the formation of root tubercles, but these substances could not replace the 

 ordinary nutritive materials. The use of calcium carbonate increased the pro- 

 duction of tubercles and tubercle nitrogen at least 33 per cent. A similar 

 result was obtained in one experiment with gypsum. 



The method of using these materials was as follows: Immediately after the 

 treatment of the seed with the tubercle bacteria cultures in milk, 1 per cent 

 peptone, and 1 per cent grape sugar, a small amount of chemically pure calcium 

 carbonate and gypsum was sprinkled on the seed, which was stirred until each 

 seed was covered with a light coat of the powdered material. 



The author considers the method of inoculation of leguminous plants with 

 pure cultures of root tubercle bacteria to be a practical, cheap, and safe method 

 of insuring that each kind of leguminous plant will have the required tubercle 

 bacteria, and that the method can be used to advantage in many cases, as, for 

 example, when cultivating new land for the first time, in case of introduction of 

 new leguminous crops, and with or 10 year rotations of crops. 



A case of failure of inoculation to increase the yield of soy beans is reported, 

 but an examination of the product showed a considerably higher content of 

 nitrogen in the inoculated than in the uninoculated plants. 



An experiment by a farmer showing the beneficial effect of inoculation on 

 peas is briefly rei)orted. 



Process of growing and distributing nitrogen-gatliering bacteria, G. H. 

 Earp-Thomas {U. 8. Patent 865.965, Sept. 10, 1907; ahs. in Jour. Soc. Chem. 

 Indus., 26 {1901), No. 20, p. 1100). — The method and apparatus used in this 

 process for producing root tubercles on various leguminous plants and preparing 

 culture media from these tubercles are described. 



The ferments of the soil and the nutrition of plants, D. Hermenegildo 

 GoRRiA {Mem, R. Acad. Cien. y Artcs Barcelona, 3. ser., 6 {1901), No. 20, pp. 

 50). — This is a general review of the progress and present status of investiga- 

 tion on this subject. 



A comparison of chemical methods with field tests for determining the 

 fertilizer requirements of soils, H. Snyder {Minnesota 8ta. Bui. 102, pp. 

 35-3S). — The amounts of phosphoric acid and potash soluble in fifth-normal 

 nitric acid in 21 different soils on which fertilizer tests with wheat and corn 

 were carried ou are reported. 



