18 EXPERIMENT STATION RECORD. 



piersisteuce, their relation to health, their damage to natural water resources, 

 and the best methods of disposing of thorn, imrifyinf; thoin, or recovering valu- 

 able materials contained in them." 



Attention is called to the fact that " a large amount of fertilizer is made 

 from slaughterhouse wastes, such as blood, waste meat, bones, hoofs, hair, 

 tainted meat, diseased animals, and taid<age or residue from rendering and 

 glue-making processes. In converting these substances into commercial ferti- 

 lizer, blood is dried at a moderate heat and crushed to powder ; bones may be 

 ground without preliminary treatment, or they may be treated with a volatile 

 solvent or boiled with steam to remove fats and gelatin and then ground for 

 fertilizer; and tankage is dried, powdered, and mixed with other fertilizing 

 material. The vjiluable ingredients sought for in all stock are nitrogen, 

 potassium, and phosphorus." 



SOILS— FERTILIZERS. 



A study of crop yields and soil composition in relation to soil productivity, 

 M. Whitney {U. S. Dept. Agr., Bur. Soils Bui. 57, pp. 127, flg.s. 24). — This 

 study is based upon evidence presented by yields of crops in Europe and the 

 United States and on individual farms as well as upon the chemical composition 

 of the soils of the United States as compared with those of Europe. The 

 statistics for the United States are confined mainly to yields of wheat and corn 

 (luring the past 40 years. The data for chemical composition include tables 

 containing all analyses of soils which have been made in the United States by 

 the acid digestion method during the past IS years, as well as similar tables of 

 analyses of soils of various European countries. 



The author states that a careful study of the data presented appears to 

 justify the following conclusions : 



" The productivity of the newer agricultural soils of the United States and 

 of the older agricultural soils of Europe, taken as a whole and for a nation, 

 are not declining, as is popularly supi)osed. Individual farms deteriorate, and 

 soils wear out as they have always done, but as a whole it seems probable that 

 we are producing more crops per acre than formerly. This is undoubtedly due 

 to many factors ; to better and more intelligent cultivation, more and better 

 systems of rotation of crops, and, in later years, to intelligent use of fertili- 

 zers — three methods of control in the hands of every individual farmer. In 

 addition, we must recognize the increase in farm animals and stock, the im- 

 provement in seed by selection and breeding, and the inci'easing density in 

 population, which is forcing attention to more intensive methods. 



" So far as our information goes there is apparently no significant difference 

 at the present time between the composition of the older agricultural soils of 

 Europe and the newer agricultural soils of the United States with respect to 

 potash, phosphoric acid, lime, and magnesia." 



A preliminary report on the Volusia soils, their problems and manage- 

 ment, M. E. Carr (U. 8. Dcpt. Agr.. Bur. Soils Bui. 60, pp. 22, pis. 10, fig. 1).— 

 The series of soils discussed in this bulletin occupies a belt of country in south- 

 ern New York, northern Pennsylvania, and northeastern Ohio, covering an area 

 of over 10,000,000 acres, in which for the past 25 years there has been a general 

 tendency toward decline in price of land and in some cases toward actual 

 abandonment of farms. The name " Volusia," as applied to this group of soils, 

 ifc derived from a small village in Chautauqua County, N. Y., where such soils 

 were first encountered and mapped in 1901 by the Bureau of Soils. 



The bulletin " discusses fully the characteristics of these soils and their 

 capabilities, treating briefly the general soil problems encountered and their 



