FERTILIZERS. 



243 



Residuary effect of artificial fertilizers. — The residuary effect of applications of artificial 

 fertilizers in 1902 on meadow grass was studied in one trial. While the fertilizers 

 applied paid well the first year, the yields and net profits obtained in the case of tin- 

 different plats in 1903 were still greater, and in the same direction fur each plat as in 

 1902, the highest results being obtained on the plat receiving 1,000 kg. of Thomas 

 phosphate and 100 kg. of 37 per cent potash salt per hectare. 



On the effect of fertilizers on the quality of root crops. — The experiments conducted 

 with root crops during two years indicate that the quality of both potatoes and fodde r 

 beets is much more easily influenced by artificial fertilizers than that of sugar beets. 

 It is therefore important to develop varieties of other root crops containing a high 

 percentage of dry substance which are not appreciably affected by the fertilizers 

 applied, as has been done to a large extent in the case of sugar beets under the 

 encouragement of sugar factories. 



Soil analyses and their practical value. — A large number of samples of the soils used 

 on the experiments were subjected to chemical, mechanical, and petrographical 

 analyses, and the results thus obtained are discussed in detail by the author in view 

 of recent investigations on the subject of soil analysis. The following average results 

 were obtained for the various kinds of soils examined, the number of samples included 

 in the analyses for 1902 being 34 and, for 1903, 43. 



Summary results of analyses of Swedish cultivated soils. 



The practical value of soil analyses is discussed on the basis of the results obtained. 

 The determinations of nitrogen and phosphoric acid are shown to be of no particular 

 value for the class of soils examined, since practically all the soils responded to 

 applications of these fertilizing materials. As to the potash requirements of these 

 soils the author concludes that soils have different requirements according to their 

 physical character. 



The following average figures were found for the potash contents of the soils 

 examined: Stiff clay 0.25 per cent, medium clay 0.20, light clay 0.15, and sandy soils 

 0.10 per cent. A deficiency of potash may be determined by comparing the per- 

 centage found with these figures. The crop to be grown and the weather conditions 

 are, however, important factors in determining whether a soil will respond to an 

 application of potash. 



On the lime content of Shane soils. — Most of the soils analyzed were examined for 

 their content of lime as carbonate, assimilable lime (obtained by digestion with a 

 10 per cent ammonium-chlorid solution on a steam bath for 3 hours), and lime sol- 

 uble in cold dilute hydrochloric acid. Without discussing the results obtained, 

 which are not considered sufficiently numerous by the author to permit of definite, 

 final conclusions being drawn, the following summary table is reproduced showing 

 the average lime content in Skane soils of different physical characteristics: 



