952 EXPERIMENT STATION RECORD. 



The material is said to have considerable value as a weed exterminator and 

 insecticide, especially for grape phylloxera, when used at rates of 1,200 to 3,000 kg. 

 per hectare. 



Crude ammonia, A. Grau {Jour. Agr. Prat.,n. ser., 11 (1906), No. 3, pp. 78-80). — 

 The agricultural value of this product (see preceding note) is discussed and direc- 

 tions given for its use. 



Analyses are reported which show a variation in total nitrogen content of 3 to 7 per 

 cent. Tests which have been made of it show that it gives best results on light soils 

 in which nitrification is most active. It is safest to apply it in December or January 

 on land that is to be seeded in the spring. It gives good results on beets and pota- 

 toes when applied at rates of 1,000 to 1,200 kg. per hectare, and on oats at rates of 

 500 to 600 kg. and lightly harrowed in. 



Analysis of nitrate of soda, E. Bensemann (Ztscltr. Angew. Chem., 18 (1905), 

 No. 50, pp. 1972-1974). — The author sets forth in complete and orderly form his 

 method of examining this substance, which has been given in a number of previous 

 articles (E. S. R., 17, pp. 7, 218). 



Acid versus basic phosphatic fertilizers, W. F. Sutherst {Chem. News, 92 

 (1905), No. 24-03, pp. 274, 275). — It is stated that when superphosphate is added to a 

 soil containing excess of lime phosphates are formed which are insoluble in water 

 but soluble in dilute organic acids, and if alumina and oxid of iron are in excess of 

 lime a still further reversion to insoluble forms results. 



When basic slag, however, is used a reverse reaction occurs. For this reason, 

 therefore, the author concludes that basic slag should be a more valuable fertilizer 

 generally than superphosphate, although slower in action because it is not so per- 

 fectly distributed as the reverted superphosphate. Comparative tests of superphos- 

 phate, basic slag, and basic superphosphate (superphosphate supersaturated with 

 lime) on mangolds are briefly reported, showing that the increased yield with the 

 basic phosphates was greater than with the superphosphate. 



On the fertilizing" action of certain accessory compounds in slag's, Guffroy, 

 Crepeaux, and Milon (Rev. Gen. Agron., 14 (1905), No. 10-11, pp. 461-464; Bui. 

 Soc. Nat. Agr. France, 65 (1905), No. 6, pp. 479-483). — A series of pot experiments 

 is reported which were designed to determine especially the fertilizing value of the 

 silica and manganese occurring in phosphatic slags. 



Comparative tests were made with wheat, buckwheat, and clover of ordinary 

 Thomas slag containing 8.41 per cent of silica and 3.87 per cent of manganese oxid, 

 and of carefully separated crystals of tetraphosphate and of silicophosphate, using 

 the latter either alone or with the addition of substances necessary to approximate 

 the composition of natural slag. The amount of complete artificial slag furnishing 

 78.1 gm. of phosphoric acid (the amount used in each experiment) contained 42.05 

 gra. of silica and 19.35 gm. of manganese. The low-silica slag, furnishing the same 

 amount of phosphoric acid, contained 4.72 gm. of silica, and the low-manganese slag 

 7.17 gm. of manganese. 



The results show that in case of buckwheat the absence of silica retarded maturity 

 and reduced the yield of straw as well as the weight of the floral envelopes and 

 branches. In case of wheat the absence of silica resulted in retarding the heading 

 and flowering, but was apparently without effect upon the yield. The efiect upon 

 strength of straw was not appreciable. The growth and yield of clover were appre- 

 ciably reduced in absence of silica in the fertilizer. The absence of manganese from 

 the fertilizer produced results similar to those obtained in case of silica as regards 

 the growth and yield of buckwheat, except that they were less marked. The ana- 

 tomical structure of the plant, however, was affected to a greater extent by the 

 absence of manganese than of silica, Like results were obtained with wheat and 

 clover. 



