SOILS FERTILIZERS. 741 



During the calendar year L904, 28,444 square miles, or 18,204,160 acres, were sur- 

 veyed and mapped on a scale of 1 in. to the mile. Prior to that year the Total area 

 surveyed and mapped was tin. 411 square miles, or 38,663,040 acres. The average 

 cosl of the \\<>rk in 1004 was $2.43 per square mile. The total ana surveyed and 

 mapped up to .Inly I, L905, was 99,408 square miles, or 63,621,120 acres, distributed 

 among 43 States and Territories. 



It is stated thai "the surveys have been so distributed thai nearly ever) promi- 

 nent agricultural interest has been touched, and the soils of some pari of every 

 important agricultural region have been studied. Aside from the specific problems 

 which affect individual areas, there bave been developed a number of vital problems 

 which concern wide extents of agricultural land," such as the classes of soils espe- 

 cially adapted to sugar beets, tobacco, early vegetables and fruits, corn, grapes, rice, 

 apples, small grains, grasses, etc., and the reclamation of alkali lands. 



"About 400 different types of soil have been encountered by the Soil Survey since 

 the beginning of its held work in L899. These soil types bave been studied and 

 classified with a view to ascertaining the particular crops which each type is best 

 suited to produce. They have also been studied from the double standpoint of 

 meeting the local needs and of placing the particular type not only in its true rela- 

 tionships to the area in which it occurs, but also in its proper place in the general 

 classification of the soils of the United states. Holding these two objects in view. 

 the study of the soils through the held work is coming to have two primary objects. 

 The first of these, the discovery of the best crops for each soil, is known as crop 

 adaptation. The second, or the study of the method by which each soil may be 

 induced to grow the largest economical crop, is known as the soil fertility or the soil 

 management problem, in addition, various local problems are encountered in 

 nearly every area." 



It is explained that the classification of soils used in this work is based mainly on 

 texture, structure, organic matter content, and physiographic relationships. "In 

 the classification employed by the Bureau of Soils tin' aim is to secure a simple, gen- 

 eral system, which shall express those facts with regard to soils which an- easily 

 recognizable by a person possessing ordinary powers of observation and no unusual 

 knowledge either of classifications or of soils. For this purpose the common names 

 of soils used by the general agricultural public are adopted and defined for use in 

 the Soil Survey reports. Owing to the fact that in different localities soils of the 

 same texture will receive slightly different names, it has been found necessary to 

 define rather carefully what is meant by a clay, a loam, or a sand. Thus, in regions 

 where the heavy day or clay loam soils predominate a somewhat sandy soil i- very 

 often considered to be a real sand, while if it were compared with the -oils of a 

 sandy locality it would he considered and would he spoken of as a rather heavy loam. 



"Through the use of its standard method of mechanical analysis, which determines 

 the amounts of the different-sized particles found in a soil, the Bureau aims to elimi- 

 nate these local differences in soil naming, in order that a uniform standard, such as 

 may he used both for scientific and practical purposes, may become common through- 

 out the regions where surveys are made. The naming of the soils is not intended to 

 introduce confusion, hut rather to avoid the use of local designations which may 

 mean one thing in one place and another thing in a different place." 



It is stated that "in order that the vast amount of valuable information which has 

 been secured by the experiment stations may he made of the most direct application 

 to each farming community within the State served, it is necessary for the farmer to 

 know not only the details of any particular experiment, hut also for him 'to he able 

 to judge whether his own farm contains the types of soil upon which the experiment 

 has been carried on, and whether it lies within the same general climatic belt as the 

 experiment station itself. If he can he assured of these two facts, it is then pos- 

 sible for him to derive the greatest benefit from the results of any particular experi- 



