soils — FERTILIZERS. 1049 



regards nitrification, nitrogen assimilation, and the decomposition of calcium cyana- 

 mid, l»nt was practically without effect on denitrification and decomposition of bone 

 meal and urea. It is concluded thai water to the extenl of from 60 to s <> per cenl of 

 the water-holding capacity of the soil is required for the uninterrupted progress of 

 the various changes in the nitrogen of the soil. 



rn these investigations soil extracts were used as a culture medium with g 1 



results. These extract- were prepared by boiling 1 kg. of soil for 2 hours with 2 

 liters of tap water. The solution, evaporated to a volume of about 800 <•<■.. was 

 cleared up with talc and filtered, and the filtrate was evaporated until it contained 

 about <).4 per cent of inorganic constituents, in this way I kg. of soil gave as a rule 

 about 600 cc. of neutral extract containing 0.4 per cent of inorganic and 0.6 per cenl 

 of organic constituents. The nitrogen content was about 0.02 per cent and the solu- 

 tion was almost entirely free of phosphoric acid. Excepl in the ease of the experi- 

 ments with bone meal, therefore, about 0.5 per cenl of dipotassium phosphate was 

 added. In the experiments reported this extract was inoculated with soil, using the 

 latter at the rate of L0 gm. of s«»il to LOO cc. of solution. 



Report of the chemical laboratory of the Ploti Agricultural Experiment 

 Station, P>. M. Welbel ( GhodXcknuii Otchet Ploty. Selsk. Khoz. Opuitn. Stantzit, 10 

 (1904), pp. 75-120; abs. in Cenlbl. Agr. Chem.,35 I 1906), No. :. pp. 73-76 . — A con- 

 tinuation and extension of previous work | E. S. Et., 16, p. 552) on atmospheric pre- 

 cipitation, lysimeter observations, and experiments in vegetation boxes is reported. 



The report deals with studies of the adaptability of lysimeters to the investigation 

 of questions relating to the ha la nee of water and nitrogen in the soil as influenced by 

 variations in precipitation, methods of culture, manuring, etc. Three -roups of lysim- 

 eters installed at the station and the kind of investigations for which they are 

 used are described. It lias been found that the method of construction and of filling 

 the lysimeters has a most important bearing upon the results obtained. 



Special attention has been given in the experiments with the Lysimeters to a com- 

 parison of the influence of black fallow and green fallow <>n the water and nitrogen 

 content of the soil. Black fallow as practiced in these experiments consisted of cul- 

 tivating the soil and allowing it to lie idle until the following fall. Green fallow 

 consisted in allowing the land to lie without cultivation from one summer to the 

 next. More water accumulated in the lower layers of tin- black fallow soil than in 

 those of the green fallow, the reverse being true for the upper Layers of the soil, hut 

 in the latter case the differences were very small. 



The drainage was greater in case of the black fallow than in case of the green. 

 There was a greater accumulation of nitrates and greater Loss in drainage in the black 

 fallow than in the green. The losses in the drainage were, however, more than 

 made good by nitrogen compounds brought down from the air, aggregating 4.5 kg. 

 of nitrogen per hectare annually. During three years of observation the application 

 of barnyard manure increased the production of nitrates ( nitric nitrogen i in the soil 

 120 kg. per hectare. During the same period soil hearing alfalfa produced 50.22 kg. 

 of nitric nitrogen more per hectare than soil not bearing alfalfa. 



Some field notes on soil inoculation, II. N. Starnes i Georgia Sia. Bui. 71, pp. 

 9l-l0-'>, ph. 12). — The present status of knowledge regarding soil inoculation for 

 legumes is briefly reviewed and experiments with commercial cultures of nitrogen- 

 fixing bacteria on cowpeas grown in an isolated field of typical ret 1 -day land in a low 

 state of fertility are reported. 



The experiments were made on fertilized and unfertilized areas of this soil. The 

 results do not indicate any particular advantage from inoculation. "In yield of 

 vines an increase appears i er acre of L75 lbs., or about :"> per cent, in favor of tin- 

 untreated over the inoculated plats, while in the yield of peas the difference is 

 reversed, there being apparent an increase of 35 lhs. per acre, or something tees than 

 5 per cent, in favor of the inoculated plats." 



