18 BULLETIN 142, U. S. DEPARTMENT OE AGRICULTURE. 



MIAMI FINE SAND. 



Areas of the Miami fine sand have been encountered only in Co- 

 lumbia and Jefferson Counties, Wis. The total area mapped thus 

 far amounts to 47,296 acres. 



The Miami fine sand consists of a light-brown, loose, incoherent fine 

 sand, which is low in organic matter. At about 9 to 10' inches in 

 depth the material is light yellow, becoming lighter in color with 

 depth, until at 30 to 36 inches it is almost white. The till bed, con- 

 sisting of a mixture of sand, gravel, silt, and bowlders, is encountered 

 at depths of 4 to 6 feet. Small quantities of limestone gravel and 

 bowlders occur on the surface and throughout the soil section, but are 

 seldom sufficiently numerous to interfere with cultivation. 



The type is subject to some variation. On the lower slopes and 

 in depressions the surface is darker and contains a larger amount 

 of organic matter than the typical soil. Such areas are slightly 

 loamy and have a somewhat higher agricultural value than the re- 

 mainder of the type. In a few places a sticky sand is encoun- 

 tered at depths of 30 to 36 inches. A few gravel beds are scattered 

 throughout the type, and such deposits have only a shallow surface 

 covering of soil. Exposed areas are sometimes wind drifted, small 

 dunes being formed. In general the Miami fine sand is both coarser 

 in texture and lower in agricultural value than the Miami fine sandv 

 loam, with which it is closely associated. 



The topography varies from gently rolling to rolling. The sur- 

 face is sometimes broken by sand dunes and depressions, though 

 rarely to such an extent as to render cultivation impracticable. 

 Owing to the loose, open structure of the material and to the sur- 

 face configuration, the natural drainage is excessive and the soil as 

 a whole is droughty. There are a few kettle-shaped basins and dune 

 depressions which are not connected with drainage channels, and 

 even in these places the drainage is usually sufficient, owing to the 

 sandy nature of the deeper subsoil. Except during the heaviest 

 rains, storm waters are rapidly absorbed by the soil and danger from 

 erosion through surface run-off is reduced to a minimum. 



The type is largely of glacial origin, being derived from the 

 weathering of the glacial till, somewhat modified by wind and 

 stream action. The weathering of the limestone fragments in the 

 underlying till has a tendency to correct any acidity existing in the 

 soil material, though this is often counteracted by leaching, leaving 

 the surface soil more or less acid. 



The original forest growth consisted chiefly of white, red, and 

 bur oak, with some hickory and hazel brush. All of the merchant- 

 able timber has been cut, but the scrubby growth of oak and hazel 

 bushes has been allowed to remain on a few of the poorest areas of 

 the type. 



