2 BULLETIN Ml, H. S. DEPARTMENT OF AGRICULTURE. 



Another distinction which is of general but not quite universal 

 application, is that the subsoils of the different types of the Clyde 

 series, particularly the subsoils of the more extensive and heavier 

 loam and clay soils, have been found to be calcareous. Many analyses 

 of these subsoils have been made, which disclose from approximately 

 1 per cent of lime carbonate to as much as 25 per cent of that mate- 

 rial. Usually the more sandy members of the series are not so well 

 supplied with lime carbonate as the heavier textured types. 



Tn their natural condition practically all the different soils of the 

 Clyde series in all occurrences which have been encountered are 

 rather poorly drained. They require artificial drainage to become 

 of agricultural use but are then very productive soils for the growing 

 of the staple farm crops of the region in which they occur and for 

 the production of special crops where market facilities are favorable. 



GEOGRAPHICAL DISTRIBUTION. 



All of the known occurrences of the soils of the Clyde series are 

 localized within the territory immediately to the south of the Great 

 Lakes. The largest areas are to be found in the Maumee Valley in 

 Ohio and Indiana ; in the valley which stretches to the southwest 

 from the shores of Saginaw Bay, in Michigan ; and along the shores 

 of the St. Clair Eiver, Lake St. Clair, and the Detroit Kiver in south- 

 ern Michigan. The latter region is a connecting strip between the 

 two larger areas. In addition there are considerable areas of soils 

 of the Clyde series in northern and western New York, associated 

 with the glacial lake deposits of the St. Lawrence Eiver Valley and 

 the Lake Ontario Plain: in northern and central Indiana, associated 

 with the great glacial river terraces of the Kankakee and other rivers ; 

 and in southeastern Wisconsin, in a glacial lake area which extends 

 from the southern end of Green Bay to the vicinity of Fond du Lac. 

 (See fig. 1.) These areas include all of the most extensive localities 

 within which soils of this series have been encountered, and within 

 which additional large areas may be expected to be mapped as the 

 work of the Soil Surve}^ progresses. 



There are, however, mairy smaller isolated areas of the soils of the 

 Clyde series which are found in the smaller basins, drained lake 

 areas, and swampy terraces of glacial outwash material which occur 

 throughout the upland portions of the States bordering the Great 

 Lakes. Although such areas may be individually of limited extent, 

 their aggregate area will ultimately be found to be very large. 



In addition many small disconnected areas of the soils of the 

 Clyde series are found in low hollows and depressed level areas 

 within the glaciated upland of the region immediately south of the 

 Great Lakes, particularly in western Ohio and eastern and central 

 Indiana. These areas represent tracts where the local drainage was 



