AGRICULTURAL BOTANY. 823 



The action of manganese in soils, J. J. Skinner, M. X. Sullivan, et al. 

 (U. S. Dcpt. Ayr. liul. J^.l {I'Jl-'t), pp. .li). — I'revi«nis investigations botli by the 

 Bureau of Soils and by otiiors bearing on this subject are revieweil, and pot 

 and field experinionts as well as culture experiments with extracts of good and 

 poor soils are reported- 

 It was found tbat manganese chlorid, sulphate, nitrate, carbonate, and dioxid 

 had a stimulating effect on wheat grown in an unproductive sandy loam soil. 

 The best results were obtained when the salts were applied in amounts furnish- 

 ing from 5 to 50 parts of manganese per million of soih When the maximum 

 rate named was exceeded there was no corresponding increase in growth, and in 

 some cases there were even harmful results. On productive loam the various 

 salts of manganese had no stimulating effect. 



With aqueous extracts of poor unproductive soils the manganese salts in- 

 creased oxidation and growth. In the case of productive soils oxidation was 

 increased but growth was decreased, the plants showing indications of exces- 

 sive oxidation. 



In a 5-year field test with wheat, rye, corn, cowpeas, and potatoes grown on 

 an acid silty clay loam soil manganese sulphate used at the rate of r/) lbs. per 

 acre had a harmful eft'ect on all of the crops grown. Its addition decreased the 

 oxidizing power of the soil, which at best was not very high. The acid con- 

 dition of the soil was unfavorable to oxidation and catalysis, and the catalytic 

 power was slightly, if at all, increased by the addition of manganese sulphate. 



The general conclusion is " that manganese is not profitable as a soil treat- 

 ment on soil of this nature in need of liming," 



Commercial fertilizers: Inspection 1913, B. H. Hite and F. B. Kunst 

 (West Virginia Sfa. In-^sp. Bid. 2 (WUf), pp. 39). — This bulletin givos the 

 guarantied and actual analyses of fertilizers inspected during 1913. The aver- 

 age composition of the fertilizers examined during the year was available 

 phosphoric acid 10.46 per cent, potash 2.74, and nitrogen 0.46. The corre- 

 sponding averages five years ago were 9, 2.5, and 0.41 per cent, resi^ectively. 

 The fertilizers of which analyses are reported in this bulletin are classified 

 as low-grade if the total of available phosphoric acid, ammonia, and potash 

 claimed in the guaranty falls below 12 per cent, high-grade if the sum is 14 per 

 cent or over, and medium if between 12 and 14 i^er cent. Farmers are advised 

 not to buy fertilizers containing less than 14 per cent of available plant food, 

 including at least 1.65 per cent of nitrogen. 



AGRICULTURAL BOTANY. 



The chemical dynamics of living protoplasm, W. J. V. Osterhout (Ahs. in 

 Scirnce, n. scr., 39 (WL'i), Xo. 999, p. ^92).— The author claims that by 

 measuring the electrical resistance of living tissues it is possible to follow the 

 progress of reactions in protoplasm and that it is possible to apply van't Iloff's 

 methods and formulas to protoi)lasm in its living and active condition. 



As an example of the application a brief description is given of experiments 

 with Laminaria in sodium chlorid solutions. From this experiment the author 

 concludes that " since the effect of sodium chlorid is within wide limits com- 

 pletely reversible, without production of injurj% the conception of chemical 

 dynamics here developed applies not only to reactions which produce death, 

 but also to reactions which involve no injury and which form a normal part 

 of the activity of the cell." This conclusion, it is said, is confirmed by experi- 

 ments with a variety of^other substances. 



The chemical behavior of inorganic nitrogenous plant food materials in 

 sunlight, O. Baudiscii {Vrtljschr. Xaturf. Gesell. Ziirich, 58 (1913), Xo. 1-2, 



46465°— Xo. 0—14 3 



