THE CLYDE SERIES 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 No. 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, 
