424 EXPERIMENT STATION RECORD. [Vol.43 



When agricultural lime was used with other chemical manures, the plats 

 fertilized with sodium nitrate or gypsum kept the neutralizing effect of the 

 calcium carbonate longer than the plats which had received potassium salts. 

 The application of 2,000 lbs. per acre; of slaked lime affected both the yield 

 and the soil reaction for several years, but the lime finally disappeared, 

 probably as a result of leaching and transformation. The latter apparently 

 had less effect than the former. 



Commercial fertilizer, T. R. Harney {Sci. Amer. Mo., 1 (1920), No. 5, 

 pp. 412-416, figs. 7). — A brief discussion is given of the functions of commercial 

 fertilizers and methods of manufacture, with particular reference to soluble 

 phosphates. 



Investigation of a bacterial fertilizer from a superphosphate factory, 

 Geilmann (Jour. Landiv., 67 {1919), No. 4, pp. 209-227).— Analyses and vegeta- 

 tion and bacteriological studies of a so-called bacterial fertilizer are reported. 



The analyses showed a certain content of potash, nitrogen, and phosphoiic 

 acid, but the main constituents were peat and calcium carbonate. The cropping 

 studies showed that the fertilizer did not increase the nitrogen content of the 

 soil, and had no effect as a nitrogenous fertilizer. The bacteriological tests 

 showed no stimulation of bacterial activity, either in soil or nutritive solution, 

 other than a small influence which is attributed to the calcium carbonate 

 content. 



Special [fertilizer] tests, C. B. Williams (North Carolina Sta. Rpt. 1919, 

 pp. 28-32). — Studies on the effect of different fertilizer combinations on peat 

 soils in progress at the Washington farm of the station have shown that liming 

 is the first essential treatment after drainage. The use of 2 tons of calcium 

 carbonate per acre gave better results than either 1 or 3 tons. Burnt lime so 

 far has shown no superiority over raw ground limestone, and the data indicate 

 that marl is not so efficient as other forms of lime. ' Phosphoric acid and potash 

 alone and in combination have shown no benefit and have in some cases de- 

 pressed crop yields. Nitrogen also appears to be of little value to this soil. 



Experiments at the Pender farm, to determine the best fertilizer combina- 

 tion for corn, oats, vetch, and cotton in a 3-year rotation, have show that nitro- 

 gen is the constituent most needed for better crops, and that phosphoric acid 

 has given more increase when used with nitrogen than has potash with nitro- 

 gen. Basic slag has not given as good results as acid phosphate. 



Tests at the Edgecombe farm on a 3-year rotation of corn, cotton, and 

 peanuts, with a cover crop each year, have given average results showing that 

 nitrogen and potash are the factors of first importance. 



Tests at the Iredell farm on Cecil sandy loam soil gave conclusive evidence 

 that the use of available forms of phosphoric acid and nitrogen are the main 

 controlling factors in the improvement of crops. In the rotation tests the 

 average results showed that corn every year and wheat every year with 

 fertilizers are no more exhausting upon the fertility of the soil than a 2-year 

 rotation of corn and wheat with fertilizers. By the use of legumes like red 

 clover in the rotation a marked increase in the yields of both crops is secured. 

 Inorganic forms of nitrogen were found to give better results on these soils 

 than organic forms. There appeared to be no residual nitrogen in soils treated 

 with organic forms of nitrogen. Potash used alone frequently depressed crop 

 yields. Acid phosphate gave slightly better results with cotton than soft phos- 

 phate rock. Poor results were secured with red clover without the use of 

 lime. 



In tests at the Buncombe farm phosphoric acid, nitrogen, and lime seemed to 

 be the controlling fertility factors on both bottom and upland soils. Where 



