450 EXPERIMENT STATION RECORD. 



In the majority of cases applications of lime were beneficial. On light soil poor in 

 humus and in dry seasons, however, the carbonates proved preferable to the more 

 caustic quick lime. Practical deductions regarding methods of application of different 

 forms of lime are drawn. 



The injurious effect of gypsum in vegetation experiments in zinc pots, 

 D. Meyer {Fuhling's Landw. Ztg., 54 {1905), Xo. 8, pp. 261-261).— Previous experi- 

 ments having shown that applications of gypsum resulted in a decrease in yield in 

 the case of certain crops grown in zinc pots on a soil composed of sand and 2h per 

 cent of peat, further experiments were undertaken to determine the cause and extent 

 of this action, as well- as the behavior of different crops grown under such conditions. 



Parallel experiments in zinc pots and in earthenware pots showed that the yields 

 were uniformly larger in the latter, but that different plants vary widely when 

 grown under the same conditions. The decline in yield following applications of 

 gypsum in zinc pots was especially marked in the case of leguminous. plants. The 

 injurious effect of the gypsum was overcome by applying witli it a certain amount of 

 calcium or magnesium carbonate, and was not observed when the artificial soil 

 mixture was made up of sand and 10 per cent of ordinary field soil. 



Further experiments are considered necessary to determine the exact cause of the 

 injurious effect of the gypsum and the behavior of different crops toward this sub- 

 stance under varying conditions. 



On the injurious action of gypsum in vegetation experiments in zinc pots, 

 B. Tacke (FiMing's Landw. Ztg., 54 (1905), Xo. 10, pp. 331, 332).— A brief note on 

 Meyer's article referred to above. 



The author calls attention to the earlier work of Fleischer o. and Tacke and Immen- 

 dorff h with gypsum on acid upland moor soils, which indicated that the injurious 

 effect of gypsum observed, especially in the case of leguminous plants, was due to 

 the setting free of acids to which such plants are especially sensitive. A similar 

 explanation is offered for Meyer's results, the injurious effect of the gypsum being 

 heightened in the case of the zinc pots by the action of the zinc dissolved by the free 

 acids, c as indicated by the author's experiments on acid moor soils. 



Some of the more recent investigations on the use of commercial fertilizers, 

 Rippert {Fuhling's Landw. Ztg. } 54 ( 1905), Xo. 18, pp. 608-620). — A review of investi- 

 gations relating especially to the comparative fertilizing value of nitrogen in form of 

 ammonia and nitrate and of different forms of rmosphates and potash salts. 



It is pointed out that in judging of the efficiency of a given fertilizer account must 

 be taken of a number of different factors, including geographical position, climate, 

 amount of precipitation, geological character of the soil, chemical and physical prop- 

 erties, depth of the surface soil, as well as the character of the subsoil. 



The investigations discussed include experiments by Kruger, Klopfer, and Schneide- 

 wind on the comparative fertilizing value of ammonium salts and nitrates used 

 alone or in mixture with peat or soil and applied as top dressing or mixed with the 

 soil (E. S. R., 15, p. 130; 16, p. 554); experiments at Lauchstadt on the use of phos- 

 phoric acid in connection with manure of various kinds, and on the relative value of 

 Wolters phosphate, superphosphate, and Thomas slag (E. S. R., 16, p. 654); and 

 experiments by Schneidewind, Meyer, and Wagner on the comparative value of 

 potassium sulphate, potassium chlorid, 40 per cent potash salt, and kainit, as well 

 as on the influence of the associated salts in potash fertilizers (E. S. R., 16, pp. 660, 

 760, 861). 



Analyses and valuations of commercial fertilizers, J. P. Street, W. P. Allen, 

 and V. J. Cakberky {New Jt rsey Stas. Bal. 187, pp. 21) . — Analyses of 232 samples of 



"Landw. Jahrb., 1891, p. 607. 



i' Mitt. Ford. Moorkultur, 1899, p. 175. 



c Landw. Jahrb., 27 (1898), Erganzungsh., IV, p. 259 (E. S. R., 10, p. 941). 



