520 EXPERIMENT STATION RECOBD. 



The maintenance of soil fertility. — Liming the corn crop, C. E. Thorne 

 (Mo. Bui. Ohio Sta.. 1 (1916), No. 1, pp. 28-^0).— Continuing field experiments 

 at the station previously noted (E. S. R., 32, p. 31), it was found that the 

 crop of corn was always increased by liming, whether the soil was manured or 

 not. It is stated, however, that the favorable effect of liming on Wayne County 

 soils is not obtained on all Ohio soils. At the Germantown test farm in INIont- 

 gomery County experiments on the use of fertilizers and lime on crops grown 

 in a rotation of corn, wheat, and clover on an upland clay soil showed that 

 the gain for lime would barely pay for the liming. "At the Miami County 

 experiment farm the effect of lime appears to be somewhat greater than at 

 Germantown, but considerably below that shown in Wayne County. . . . 



" While it may be doubtful whether it will pay to use lime for ordinary crops 

 in western Ohio, it will quite generally be advisable to lime the alfalfa crop." 



The cost of agricultural lime, C. W. Montgomery (Mo. Bid. Ohio Sta., 1 

 (1916), No. 1, pp. 31, 32). — The costs of obtaining agricultural lime at the Cler- 

 mont and Hamilton counties experiment farms were found to be governed 

 largely by local conditions. 



Data and discussion on the value of activated sludge as a fertilizer, E. 

 Bartow and W. D. Hatfield (En(jin. and Contract., ^ (1915), No. 22, pp. 434- 

 436, figs. 4; Jour. Indus, and Engin. Chem., 8 (1916), No. 1, pp. 17-20, figs. 4).— 

 In connection with experiments noted elsewhere (p. 591) further pot culture 

 experiments (E. S. R., 33, p. 423) with wheat on sand to determine the ferti- 

 lizing value of activated sludge as compared with that of dried blood when 

 added in amounts furnishing equivalent amounts of nitrogen are reported. 

 The sludge used contained 6.3 per cent total nitrogen, 2.69 per cent phosphoric 

 acid, 4 per cent ether-soluble matter after three hours' extraction, and 11.8 

 per cent ether-soluble matter after 16 hours' extraction. The growth of wheat 

 fertilized with sludge was much more rapid than that fertilized with dried 

 blood. 



A .second series of pot cultures comparing the sludge with dried blood, sodium 

 nitrate, ammonium sulphate, and gluten meal confirmed the results of the 

 first experiments. Plat experiments with radishes and lettuce, using equivalent 

 amounts of dried and extracted sludge, showed marked increases in crop with 

 both sludges, the results being slightly in favor of the extracted sludge. 



The results of these experiments are taken to indicate that the nitrogen of 

 activated sludge is in a very available form and that activated sludge is 

 valuable as a fertilizer. 



Activated sludge experiments at Urbana. Illinois (Engin. News, 74 (1915), 

 No. 23, pp. 1096, 1097). — The substance of this article is contained in the above. 



The value of fi.lter press cake as a fertilizer, W. E. Cross and J. A. Belile 

 (RcxK Indus, y Agr. Tucamdn, 5 (1915), No. 9. pp. S73-3S0).— The fertilizing 

 value of sirup sludge from sugar refineries is discussed, and analyses of seven 

 samples are reported which show that the phosphoric acid content varied from 

 3.04 to 7.81 per cent, the nitrogen content from 1.87 to 2.75 per cent, the lime 

 content from 2.95 to 11.2 per cent, and the organic matter content from 50.77 

 to 70.98 per cent. Three of the samples contained 5.05, 4.49. and 3.26 per cent 

 of citrate-soluble phosphoric acid. On the basis of these results and those ob- 

 tained by others it is thought that this material should be of value as a fer- 

 tilizer, especially for sugiir cane. 



Report on commercial fertilizers, 1915, E. H. Jenkins and J. P. Street 

 (Connecticut State Sta. Rpt. 1915, pt. 1, pp. 1-79). — This report discusses the 

 fertilizer situation in Connecticut, with special reference to the importance of 

 conservation and use of natural fertilizer resources, and reports and di.«!cusses 

 the results of actual and guarantied analyses and valuations of 625 samples of 



