428 EXPKHIMENT STATION RECORD. 



that the nitro-bactoriiu' did not contain littcilliis radicicoUi, thonsh (Mostridinni 

 and a Cotvus were prosont, and that tlio culture produced no tultercics on the 

 roots of lupines. Inoculation by nit^aus of soil is considered lu-eferalile to the 

 use of either nitraj,'iu or nitro-bactei'ine. 



Soil inoculation exj)erinients with nitragin and nitro-bacterine, E. Guab- 

 NEB {Jour. Lamliv., 57 H'JOD), No. 3, pp. 217-223, pis. S; ahu. in Deut, Landiv. 

 Presse, 37 ilUKI), .Vo. 2, pp. 1), 1.3, figs. 8). — I'ot experiments with white 

 lupines and s.-nid jie.is on calcareous sandy soil are reported, showin.i; that 

 both inoculatinj? materials, especially when used in connection with potash 

 and phosphoric acid, were active, the nitro-bacterine being more effective than 

 the nitrajiiu, whicli was especially feeble in action on sandy soils deficient 

 in lime. 



Further experiments on the increase of nitrogen in soils by means of free 

 living bacteria, A. Kocii (Jour. Lundw., 57 (IDOU). No. 3, pp. 26'.)-28()). — A 

 continuation of previous investigations on this subject (E. S. K., 20, p. 17) is 

 here reported, and the results obtained during the 5 years, I'lO.l to TOO!), that 

 the investigations have been in progress, are summarized. The investigations 

 dealt particularly with the effect on nitrogen fixation of adding sugars to the 

 soil and with the relative efliciency of different carbonaceous foods for the 

 nitrogen-fixing organisms. 



In pot experiments witli buckwheat, beets, wlieat, and oats grown in succes- 

 sion it was observed that the effect of increased nitrogen fixation due to the 

 addition of sugar to the soil in 1905 was evident in increased yields in 1009, 

 except in one series of experiments, in which sugar was added at the rate of 

 only 100 gm. per IS kg. of soil. In pot experiments with pure sand the rate 

 of fixation was 7.2 mg. of nitrogen per 100 gm. of sand containing 2 gm. of 

 cane sugar .during a period extending from March 4 to June 1. There was, 

 however, a decline in yield of buckwheat and mustard grown on the sand, 

 which is ascribed to the injurious effect of the products of decomposition of 

 the sugar. These injurious products remain longer in sand than in loam soil 

 and can not be of benefit in sand in rendering plant food available. 



Field experiments similar to those conducted in previous years showed in 

 case of wheat, rye, and oats grown in succession that the benefit from increased 

 nitrogen fixation due to the addition of sugar was least the first year, but was 

 marked the second and third years. That the fixation was due mainly to 

 Azotobacter was shown by experiments with a number of different kinds of 

 soil containing varying numbers of this oi'ganism. It was shown that the 

 distribution of Azotobacter is very irregular in soils, many of the soils exam- 

 ined being largely or totally deficient in the organisms. In such soils there 

 was little fixation of nitrogen. 



A comparison of mannite, dextrose, xylan, glycerin, calcium succinate, and 

 calcium butyrate as sources of carbonaceous food for nitrogen-fixiiig organisms 

 showed that only mannite and dextrose possess any particular value for this 

 puriiose. 



Investigations on the action of moor soils as a fertilizer with especial 

 reference to the nitrogen content, F. Herrmann {Ber. Physiol. Lab. h. Vers. 

 Anst. Landir. Inst. Halle, W09, No. ID. pp. 126-177) .—Feat from different 

 sources was compared with stable manure with and without the addition of 

 lime in a series of pot and field experiments. 



Peat from upland and lowland moors was used. The former contained in 

 the air dry condition 1.12 per cent of mineral matter, 0.17 per cent of lime, 

 0.04 Y)er cent of phosphoric acid, and 0.86 per cent of nitrogen. Two samples 

 of the lowland peat contained in the air dry condition 17.64 and 17.38 per 

 cent, respectively, of mineral matter. 6.59 and 6.19 per cent of lime, 0.35 and 



