No. 3, December, 1920) SOIL SCIENCE 205 



very small amount of acidity had developed and very little potassium had been made soluble. 

 \\ hen no organic matter was added 1 he amount of acidity and soluble sulphates were no greater 

 than misfit be accounted for by the natural oxidation of sulphur.- Addition of ferrous and 

 aluminum sulphates in small amounts failed to stimulate sulphofication, while calcium car- 

 bonate added to the sulphur-manure-soil compost stimulated action in early stages but the 

 end result was no greater than without it. — More water-soluble potassium was formed from 

 the high-potassium green sand hut a larger percentage of total potassium present was liber- 

 ated in the composts containing the low-potassium green sand. The total amounts of potas- 

 sium recovered in aqueous extracts from the composts containing manure varied from 0.1 to 

 41.3 per cent of the total initial amounts present. — Composting of green sand, or of soil rich 

 in potassium, with sulphur and manure may prove a practicable method of obtaining avail- 

 able potassium from comparatively insoluble materials.— D. Reddich. 



1378. Neller, J. R. The potential biochemical activity of the spores of soil bacteria. 

 Soil Sci. 9: 329-340. 1 fig. 1920.— Infusions from five successive layers of the upper 64 cm. 

 of soil were heated to 85°C. for 10 minutes. This treatment destroyed 91.3-98.4 per cent of 

 the organisms originally present. Inoculating with heated infusions produced 39-46.6 per 

 cent as much ammonia in 7 days and about 77 per cent of the CO2 produced by inoculating with 

 unheated infusions. The bacterial spores of the soil are capable of energetic activity when 

 supplied with sufficient food and moisture. — W. J. Rdbbins. 



1379. Plymen, F. J., and Bal. The biological aspects of wheat cultivation on embanked 

 soils. Agric. Jour. India 15: 289-300. 1920. — Cultivation and other means of increasing aera- 

 tion of the black flood soils produce a condition favorable to crop production. The soils 

 possess good power for ammonification and N fixation but are slow in nitrification. Nitri- 

 fication increases when the rainy weather cultivation is performed. Lack of available nitro- 

 gen or the presence of some deleterious substance formed under anaerobic conditions is 

 attributed to be the cause of crop failure. — /. J. Skinner. 



CROP FERTILIZATION 



1380. Blair, A. W. Utilizing soil potash by means of intermediary crops. Proc. Soc. 

 Promotion Agric. Sci. 39: 69-74. 1919. — New sources of potash discovered by chemists in 

 the United States have made available "not over one-fourth of the pre-war consumption" of 

 potash fertilizer. Most of the soils in the United States are well supplied with potash in 

 the form of mineral materials but much of this potash is unavailable or only slowly available 

 to the growing crop. In a study of the problem of making this supply of potash available it 

 was found that the dry matter of rape and field peas contained an unusually large percentage 

 of K 2 0. The growing of such crops as a preparation for corn, alfalfa, or small grain is sug- 

 gested as a means of suppljdng the desired potash in available form. — H. N. Vinall. 



1381. Conner, S. D., and E. N. Fergus. Borax in fertilizers. Purdue Univ. Agric. Exp. 

 Sta. Bull. 239. 15 p., 4 fig- 1920. — Borax injury to corn resulting from the use of Searles Lake 

 potash in Indiana during 1917-1919 is described. Field tests conducted at two points in 1919 

 showed that from 0.5 up to 4 pounds of borax per acre produced injury when drilled in the row 

 with corn, that 16-18 pounds worked into the entire surface soil produced no injury, and that 

 the damage was less in clay than in sand or muck, less in neutral than in acid soils, and less 

 when rains accompanied the application. Borax causes injury by retarding or preventing 

 chlorophyll formation. Bleaching, tip burn and wilting are the symptoms. Soybeans are 

 more sensitive to borax than corn, while wheat, oats, rye and corn are equally susceptible. 

 Only the Searles Lake potash contained enough borax to cause injury. Field tests showed 

 that American potash fertilizer was equivalent to the German product in fertilizing val 



A brief resume of the literature is presented.— Max W. Gardner. 



1382. Voelcker, J. Augustus. The Woburn Experimental Station of the Royal Agricul- 

 tural Society of England. Field experiments, 1919. Jour. Royal Agric. Soc. England, 80: 



