FEETILIZERS. 427 



on population and farm crops, early use of fertilizers, chemical investigation of soils, 

 Imcteriological investigation of soils, physical conditions and soil investigations, and 

 important soil investigations and their utility. It is a review of progress in this line 

 of investigation during the nineteenth century. 



" Probahly the most important immediate results of practical utility to be derived 

 from these soil investigations are the mapping of large areas in important agricultural 

 districts. In the irrigation districts these investigations point out any source of alkali 

 which is to be feared, the cause of the accumulation, and give a basis for the intelli- 

 gent underdrainage when necessary to remove the salts and seepage waters. In all 

 cases the majis show the various types of soils, and the reports accompanying them 

 explain the differences in these soils so far as possible, and describe their character- 

 istics. The greatest value of these maps will be in the possibility of intelligent special- 

 ization. When a light loam is seen adjoining a heavier loam or clay the methods of 

 cultivation or cropping should not be alike, and will not be when the farmers realize 

 the importance of the differences in the properties of the soils. It is generally a waste 

 of energy to attempt thus to compete, or use the same methods, or even to grow the 

 same crops oftentime on soils of such different texture. The safest and altogether 

 most practical thing is to recognize the differences in the soils and the peculiarities of 

 each; use each for the particular crop or class of crops best suited to the conditions; 

 then attempt to improve each by the controlling factors, which are quite sure to be 

 revealed in the experience of changing climatic conditions and the development of 

 crops in the course of 2 or 3 years. The development of plants is a sure and 

 safe guide generall}^ to an experienced person as to the condition of the soil. This 

 specialization is unquestionably developing in this country as a result of competition 

 and of social conditions, and reliable and detailed soil maps will be the best possible 

 l)asis for this purpose." 



On marsh formation on the west coast of Schles-wig and on the character 

 of the reclaimed lands, Becker {Jour. Landv., 48 {1900), No. 2, pp. 123-14-5, figs. 

 2). — The formation and character of these lands are described and physical and 

 chemical analyses and pot tests of samples of the soil are reported. 



Dunes and their culture {Deut. Landw. Fresse, 27 {1900), Nos. 40, pp. 499, 600, 

 fi'jx. 4; 44, p. 551, figs. 3). 



FERTILIZERS. 



Alfalfa as a fertilizer, B. C. Buffum ( Wyoming Sta. Bid. J^Jf., j)j). 

 9J-106, j/l.'i. :3). — This l)ulletiii discusses briefi}^ the fertilizer require- 

 ments of soils of arid regions, especially of Wyoming, and the value 

 of alfalfa for increasing the nitrogen of the soil, improving the tilth, 

 and destroying weeds; and gives the history of an acre plat on the 

 Laramie Plains, one-half of which had been in alfalfa since 1893 and 

 the other half in other crops. The whole plat was plowed in the fall 

 of 1898 and seeded in the spring of 1899 to wheat, oats, and potatoes, 

 one-half of each of these crops being on the alfalfa land and the other 

 half on the part which had been under rotation with other crops. The 

 main results obtained are summarized as follows: 



" The value of alfalfa harvested from one-half acre of land for 5 years at Laramie 

 was about $50 more than the cost of producing it. 



"The value of potatoes and grain from an adjoining half acre for 5 years was about 

 $-14 more than the cost of producing at local prices. 



"When the alfalfa land was plowed and planted to wheat it produced $8 to $12 more 

 value in wheat per acre than the land which had grown potatoes and grain before, 

 11989— No. 5 3 



