124 EXPERIMENT STATION RECORD. [Vol.43 



It is estimated that in tlie northern division of tlie country cut-over hinds 

 alone total an area of 22,483,000 acres, of which 10,237,000 acres arc apparently 

 considered to be available for community .settlement. The acreage of swamp 

 and overflow lands in the north is estimated to be 22,866,000 acres, of which 

 1,176,000 acres are available for settlement. 



Relation of bacteria to soil productivity, J. C. Beavers (Canad. Power 

 Farmer, 25 {1920), No. S, pp. 16, 18, 20, fig. i).— This paper, a contribution from 

 the Indiana Experiment Station, is a popular discussion of the functions of 

 Ijacteria in soil in promoting soil fertility and of the influence of different 

 cultural treatments thereon. 



The periodic influence of the time of year on the process of nitrifica- 

 tion, O. Lemmermann and L. AVichers {Centhl. Bakt. [etc.], 2. Abt., 50 (1020), 

 No. 1-4, pp. 33-43, fig. 1). — Experiments on nitrification in soils are reported, 

 the results of which are taken to indicate that the hitherto advanced proofs of 

 a direct periodic influence of the time of year on the life activities of soil 

 organisms 'independent of temperature and other physical weathering influences 

 are insufficient. It is stated that all previous data correspond with the results 

 of these experiments. 



It is concluded that if a direct influence of time of year could be established, 

 the already great number of unknown and uncontrollaljle factors in soil l)ac- 

 teriology would be increased. 



The occurrence of " volutin " in Azotobacter chroococcum, E. W. 

 Schmidt (Centhl. Bakt. [etc.], 2. Abt., 50 (1920), No. 1-4, pp. 44, ^.5).— Experi- 

 ments are briefly reported which indicate that A. chroococcum contains consid- 

 erable volutin. This is in contradiction of previous findings of others. 



Handling farm manure, F. L, Duley (Missouri Sta. BUl. 166 (1919), pp. 

 3-29, figs. 13). — This bulletin deals with the conservation and proper use of 

 farm manure in accordance with practice found best under Missouri conditions. 



It has been found that manure should be spread while fresh, if possible, and 

 that plenty of bedding should be used to absorb the liquid manure. INIanure 

 exposed to the weather four or five months may lose from one-third to one-half 

 of its plant food. Fermentation during storage may be reduced by keeping the 

 manure compact and moist or by storing in concrete pits under cover. It is 

 stated that for the average farm, applications of from 6 to 8 tons of manure per 

 acre once in a rotation should give satisfactory returns, and that the careful 

 farmer should be able to return manure at the rate of about 2 tons per acre 

 annually to his cultivated land. Manure is usually best applied before corn 

 and plowed under or used as a top-dressing foi* wheat. It may often be applied 

 with profit to hay or grasslands. * 



" According to the IMissouri experiments and at present prices for farm 

 products, manure is worth more than $4 a ton when spread on the land. At 

 normal prices it is worth approximately $2.50 a ton. To get the most profit 

 from manure and at the same time most nearly maintain a well-balanced con- 

 dition of soil fertility, it is good practice to reinforce each ton of manure with 

 25 to 40 lbs. of acid phosphate or 40 to 80 lbs. of rock phosphate. When acid 

 phosphate is used it may be applied with the manure or it may be drilled when 

 seeding some small grain crop in the rotation." 



The effect of fertilizer salts treatments on the composition of the soil 

 extracts, C. H. Spurway (Michigan Sta. Tech. Bui. 45 (1919), pp. 3-18). — Data 

 are presented to show the effects of additions of potassium chlorid, acid phos- 

 phate, hydrated lime, calcium sulphate, sodium chlorid, sodium nitrate, 

 tricalcium phosphate, monocalcium phosphate, and calcium carbonate to tAvo 

 alkaline and two acid sandy-loam soils on the composition of their water 



