948 



EXPERIMENT STATION RECORD. 



2. Abt., 15 {1906), No. 21, p. 643). — Experiments with poudrette are reported which 

 show that nitrification went on rapidly at first, but that later when the soil became 

 drier and warmer denitrification set up. The bacteriological side of the question is 

 nol considered, but the relation of the use of poudrette to the development of smut 

 in corn is discussed. 



A study of nitrification of some organic fertilizers, Guillix (Bui. Soc. Nat. 

 Agr. France, 66 (1906), X<>. 1, pp. 85-94, fig. 1 )- — Studies of relative rate of nitrifica- 

 tion in soil and comparative fertilizing value in pot experiments with oats are 

 reported for dried blood, wool waste, roasted wool, crude ammonia obtained from 

 evaporation of ammoniacal gas liquor, wine lees, and "galalith," a refuse from the 

 preparation of various small articles from hardened casein. The amounts of organic 

 nitrogen transformed into nitric nitrogen during 3 months when the different 

 materials were mixed with a suitable soil at rates furnishing 1 gm. of nitrogen per 

 kilogram of soil are shown in the following table: 



Nitric nitrogen formed (luring three months with different organic fertilizers furnishing 1 gm. 



of nitrogen. 



Dried blood 



Galalith 



Wool waste 



Roasted wool — 

 Crude ammonia . 

 Wine lees 



At end of 

 one month. 



Grains. 



0.168 



.005 



.019 



.090 



At end of 



three 

 months. 



Grams. 

 0. 345 

 .217 

 .230 

 .309 

 .014 

 .070 



At end of 



five 

 months. 



Grams. 

 0.634 

 .600 

 .373 

 .536 

 .199 



The dried blood nitrified most readily. The galalith nitrified very slowly at first, 

 but afterwards more readily. The wool waste was much inferior to the roasted wool 

 as regards rate of nitrification. The crude ammonia nitrified very slowly during the 

 earlier stages of the experiment, but with a higher temperature nitrification was 

 quite rapid. The nitrification of the wine lees was very unsatisfactory. The order 

 of efficiency of the different fertilizers m pot experiments with oats was as follows: 

 Dried blood, roasted wool, galalith, wool waste, wine lees, crude ammonia. 



In discussing these experiments, A. C. Girard called attention to the fact that this 

 method of comparing fertilizers was inaugurated by Miintz and Girard more than 15 

 years ago and that it has been shown to be a valuable method of determining the 

 relative value of organic nitrogenous fertilizers. 



On the importance of nitrification for cultivated plants, W. Kruger 

 (Landw. Jahrb., 34 (1905), No. 5, pp. 761-782, jrts. 3; abs. in Chem. Centbl, 1906, 1, No. 

 1, pp. 71, 72). — The general object of the experiments here reported was to deter- 

 mine whether ammonia is directly assimilated by cultivated plants or whether it 

 must first be transformed by nitrification. 



The experiments, which were begun in 1899, were made in pots containing a mix- 

 ture of 50 per cent sand and 50 per cent ordinary farm soil. One series of pots was 

 sterilized and another was not sterilized. They all received the same basal applica- 

 tion of phosphoric acid and lime. Some in each series received no nitrogen, some 

 nitrogen in the form of ammonium salts, and others nitrogen in form of nitrate of 

 soda. The crops experimented with included mustard, oats, barley, potatoes, and 

 fodder beets. The data recorded include the yields and nitrogen content of the 

 plants, as well as qualitative tests of water extracts of the soils. 



The results show that mustard, oats, and barley derive nitrogen from ammonium 

 salts and nitrates with equal facility, and that for such crops these two sources of 

 nitrogen are equally valuable. Potatoes appear to prefer ammonia to nitrate as a 



