1140 EXPERIMENT STATION RECORD. 



The solubility of phosphoric acid in sugar-beet soils, J. Stoklasa (Bl. 

 Zuckerriibenbau, 13 (1906), Nos. 1, ]>p. 1-9; 2, pp. 17-25, pis. 2; abs. in Chem. Ztg., 30 

 (1906), No. 16, Repert. No. 4, PP- 55, 56). — The importance of carbon dioxid pro- 

 duced by micro-organisms in the soil and given off by plant roots as a means of 

 rendering the soil phosphates assimilable is discussed. 



It is estimated that 1 gm. of a humus soil contains probably 20 to 30 million micro- 

 organisms, which, with a 20 per cent water content and a temperature of 15° C, 

 are capable of producing 50 to 60 mg. of carbon dioxid per day. The most rapid 

 production of carbon dioxid occurs in the soil at the depth of 10 to 40 cm. and 

 amounts during the growing period (150 days) to 112.5 metric centners per hectare 

 (5,010.12 lbs. per acre). 



The author's observations indicate that the fine roots and root hairs of sugar beets 

 are capable of producing as much as 9(30 kg. of carbon diox # id per hectare in 60 days. 

 The carbon dioxid dissolved in water exerts a direct solvent action on the phosphates 

 of the soil. 



On the improvement of a soil relatively deficient in magnesia, T. Nakamura 

 (Bui. Imp. ('nit. Agr. Expt. Sia. Japan, 1 (1905), No. 1, pp. 30-34). — In pot experi- 

 ments with a soil containing 17 times as much lime as magnesia it was found that 

 although there was sufficient magnesia for the growth of barley plants, the addition 

 of magnesia was very beneficial. The most favorable ratio of lime to magnesia was 

 7:1, provided the magnesia was applied in the form of sulphate. 



"Since the best ratio of lime to magnesia for the growth of cereals was found to 

 be 1 :1 when magnesia was applied in the form of magnesite, it would have required 

 333 gm. magnesite per pot in order to attain the above ratio. As the best result 

 was, however, obtained when 78.72 gm. magnesium sulphate were applied per pot, 

 we may conclude that the relative value or agronomical equivalent of magnesium sul- 

 phate to magnesite is here nearly 23: 100." 



Meeting of the fertilizer section of the German Agricultural Society ( Mitt. 

 Deut. Landw. ( resell., 21 (1906), No. 7, pp. 69-74)- — Short accounts are given of the 

 discussion of the following topics: The use of commercial fertilizers in Bavaria, pres- 

 ervation of barnyard manure and its most profitable use, and the influence of defi- 

 ciency or excess of rainfall on the action of fertilizers. 



Investigations by Pfeiffer at Breslau and Immendorff at Jena on the preservation 

 of manures are summarized. The latter show that there is a considerable loss of 

 nitrogen in the stall, and this is greater if the manure is allowed to lie for some time 

 (say 7 days) under the feet of the animals than if it is removed daily. Contact with 

 already fermenting manure apparently hastens the loss of nitrogen. The loss is 

 greater both in the stall and in the heap in warm weather than in cold. 



Kainit and superphosphate gypsum used at rates of 1.5 to 2 kg. per 1,000 kg. of 

 live weight of animal were practically worthless. The use of sulphuric acid and 

 superphosphate gypsum in amounts (3 kg. per 1,000 kg. live weight) giving a per- 

 manent acid reaction quite effectively prevented loss of nitrogen, but this is not prac- 

 ticable on account of excessive cost. The use of peat litter is the most effective 

 means of preventing loss. In the experiments reported the loss of nitrogen was 

 reduced to 7.3 per cent. The loss of nitrogen was less when the liquid manure was 

 separated from the solid than when the two were mixed. 



The sale of sheep manure, F. de Barrau (Jour. Agr. Prat., n. ser., 11 (1906), No. 

 11, pp. 341-343). — A brief note on local trade in this article and on its composition 

 and fertilizing value. The following analysis is reported: Nitrogen (organic and 

 ammoniacal) 1.36 per cent, phosphoric acid 0.26 percent, potash 1.17 percent, water 

 60.33 per cent. The manure is valued especially by viticulturists. Attention is 

 called to the danger of impoverishing the farm by selling this material without 

 returning an equal amount of fertilizing material in some other form. 



