THE CLYDE SERIES OF SOILS. 35 



Niagara County, N. Y., the surface of the type ranges from 300 to 

 600 feet above sea level, while in the vicinity of Saginaw Bay, in 

 the southern peninsula of Michigan, it lies from approximately 600 

 feet to about 750 feet above tide. Other separate areas in southern 

 Michigan and northern Indiana have about the same altitude. 



In all cases the Clyde loam is either poorly drained at the present 

 time or was poorly drained prior to its occupation for agricultural 

 purposes. In practically all areas where it occurs the Clyde loam 

 constituted wooded swamps or grass-grown marshes in the days of 

 pioneer occupation, and in the majority of instances other upland 

 soils were first cleared and occupied. Later the obstructed natural 

 drainage was improved by the straightening of streams and the 

 opening of drainage ditches, and gradually increasing areas of this 

 black mucky soil have been brought under cultivation. The Clyde 

 loam in its undrained condition, wherever it is encountered, either 

 constitutes swamp not occupied for any agricultural purpose or else 

 forms pasture lands upon which cattle are grazed during the later 

 months of the summer, or where, in the treeless areas, swamp grass is 

 cut for hay. It has only been through the establishment of artificial 

 drainage that this soil has been made available for agricultural use. 



Owing to the swampy or semiswampy condition of the Clyde 

 loam prior to drainage, the surface soil is frequently found to be 

 in a puddled, compact state, sticky and impervious when wet and 

 drying out to a clodded or cementlike surface when dry. These 

 effects of poor drainage are emphasized where the finer-grained 

 material is found in lower lying areas which have been under culti- 

 vation for only a short time. In such cases the soil proper is fre- 

 quently stiff and sticky and clods badly when plowed. The con- 

 tinued cultivation of the type, however, and the long-continued 

 operation of frost upon well-drained areas tends to correct this 

 condition and to make the Clyde loam an extremely valuable soil 

 for the production of the majority of the general farm crops suited 

 to the temperate climate within which the type is most extensively 

 developed. 



In the case of the Clyde loam a larger acreage of the type is 

 devoted to the production of grass for the cutting of hay than to 

 any other crop. The type is not only well suited to produce large 

 yields, but the management of the soil and of the general farming 

 system in the areas where it occurs has brought about a crop rota- 

 tion usually consisting of one year devoted to the production of a 

 hoed crop, one or two years devoted to small grain growing, to be 

 succeeded by two, three, or even five years of grass production in 

 the course of the rotation. Because of the adoption of such long- 

 term rotations, in which the land is frequently occupied during half 

 of the entire period by the stand of grass, the acreage of this crop 



