702 EXPEKIMENT STATION RECORD. 



The article in this iind the succeed i no- nunilier of the Record, which 

 is based upon a .suiniiiarv hy Dr. P. Fireman of an article (in Russian) 

 by Sibirtzev, discusse.s this classitication. and the soil types of Russia. 

 As will be seen, it groups the soils of the world in seven main zones 

 or belts, as follows: (1) Lateritic soils, (2) aeolian or loess soils, (3) soils 

 of the dry steppes, (4) chernozem, (5) gra}' forest soils, (6) sod or podzol 

 soils, and (7) tundra soils. The grouping is more complete for the 

 northern than for the southern hemisphere, but even in the former it 

 is not claimed that the zones aiv continuous oi' imiform. This is but 

 natural, as in some cases certain soil-forming factors within the zones 

 ma}' predominate oyer the combined action of the other conditions 

 and agencies inyolyed, and thus impart special features which are not 

 distinctiye of the prevailing zonal tj^pe. Alkali soils, humus calcareous 

 soils, and marsh soils are examples of intrazonal types. 



In addition to these zonal and intrazonal soils there is a third class, 

 incomplete or azonal soils, which are composed almost exelusivel}' of 

 unaltered parent rock with little or no tine earth and humus, and which 

 stand on the borderland between true soils and rocks. In this group 

 are classed soils formed rji situ and alluvial soils. Of course, in nature 

 there must, under any conditions, be man}' transitional or modified 

 types or forms which are difficult of classijfication. The subdivision of 

 the various genetic types into groups and subgroups requires, there- 

 fore, not onh' a study of the dynamic forces which impart to the soil 

 its fundamental characteristics, but also a comparative study of the 

 changes in the composition and structure of the soil and of the parent 

 rock, that is, petrographic, physical, and chemical examinations. In 

 this respect the system of Dokouchayev and Sibirtzev harmonizes with 

 the commonly accepted classification of the German and other Russian 

 investigators, including Mayer, Schiibler, Knop, Senf t, Ramann, Feska, 

 Kostichev, and others. 



Turning from a consideration of the system followed to the results 

 accomplished, we find that the work of soil investigation in Russia has 

 been prosecuted with such vigor and thoroughness that not only has 

 Professor Sibirtzev been able to give in a recent report a soil map 

 showing in colors the areas occupied by the principal types of soils of 

 European Russia (about 22), but'also a very complete characterization 

 of these soils, including their origin and history, topographic features, 

 vegetation, climatic conditions, relation to moisture, physical and chem- 

 ical properties, and behavior under culture. An abstract of this report 

 will appear in a future luimber of the Record. As a comprehensive, 

 S3'stematic, and thorough piece of work which has been fruitful of 

 remarkable results, these Russian soil investigations are worthy of the 

 careful stud}' of all interested in the subject. They should be of 

 especial interest to American investigators, since the soil conditions 

 of Russia are to a considerable extent duplicated on this continent, a 



