THE CLYDE SEEIES OF SOILS. 59 



It is, therefore, very desirable that artificial drainage should be 

 extended in areas where it has already been begun and that steps 

 should be taken to reclaim these fertile and valuable soils in regions 

 where community soil drainage and even local farm drainage are 

 not yet practiced. The value of the reclaimed land is always suffi- 

 cient to repay the expenditure for any well-planned drainage opera- 

 tions upon the soils of the Clyde series. This has been proved by 

 the success attained in the drainage of hundreds of thousands of 

 acres of the different types. 



Many problems of engineering are involved in good tile drainage. 

 For discussion of these the person particularly interested is referred 

 to Farmers' Bulletin No. 524 of the United States Department of 

 Agriculture. Also to the Special Bulletin Xo. 56 of the Michigan 

 Agricultural Experiment Station and to numerous other experiment 

 station bulletins. 



SUMMARY. 



The Clyde series includes types with dark-colored surface soils, 

 usually well filled with organic matter, underlain by gray or mottled 

 subsoils. 



They have been formed as glacial lake sediments, as terrace de- 

 posits along glacial streamways. and as accumulations in small ponds, 

 lakes, or in other positions of obstructed drainage within the 

 glaciated region of the northern United States. The deeper sub- 

 soils of the finer grained members of the series are usually calcareous; 

 that is, they contain more than 1 per cent of lime carbonate. 



The soils of the Clyde series have been encountered in 37 different 

 areas of which soil surveys have been made, located in 7 different 

 States, and covering an aggregate area of 1,877,700 acres. 



They are chiefly found in level or depressed areas within the glacial 

 lake and river terrace province. 



Because of the level topography and of prevalent dense subsoil con- 

 ditions, the different soils of the Clyde series were usually swampy or 

 very poorly drained in their natural condition. 



Soils of the Clyde series are found at all elevations from approxi- 

 mately 250 to 800 feet above sea level, throughout the region of 

 the Great Lakes, Usually there is little topographic relief in any 

 small area and the slopes are gentle. Some members of the series 

 consist of low ridges or gently undulating plains. 



The soils of the Clyde series are divided into 11 different types 

 upon the basis of differences in texture. These range from gravelly 

 sand to clay. 



The crop adaptations of the different soils of the series are given 

 in detail in the text of the bulletin for the different localities in 

 which they occur, 



