LIGHT COLORED UPLAND SOILS. 
25 
periods when the melting ice sheets greatly increased the vol¬ 
ume of water flowing down the Mississippi River and many of its 
tributaries. The high water in the Mississippi River itself 
caused a backwater or partly ponded condition in the tributary 
streams. In these more or less quiet waters the finer particles 
now forming the soil were deposited. The coarser particles in 
the deep subsoil were deposited earlier, before the ponded condi¬ 
tion prevailed and when the current was swifter. It is probable 
that a portion of the surface material, especially close to the foot 
of the bluffs, is partly colluvial, having been washed down the 
steep slopes from the Boone and Knox silt loam areas, which 
are always found at a higher elevation. 
The gravel in the Lintonia terraces is of glacial origin. In the 
valley of Buffalo River such gravel is found as far up as Mon- 
dovi, though none is found in this valley more than a mile east 
of Mondovi. Such gravel, however, is found in the valley of 
Farrington Creek to the west of Mondovi. 
Native Vegetation .—The original timber growth on the Lin¬ 
tonia silt loam consisted chiefs of oak, with some hickory and a 
few other species. Most of the timber has been removed. In the 
ravines there is now a second growth of sumac, hazel, and other 
brush. 
Present Agricultural Development .*—Practically all the type, 
except the more eroded areas, is put to some agricultural use, 
and most of it is cultivated regularly. The land where erosion 
is most active is kept in pasture most of the time, or the grass 
may be cut for hay. The crops generally grown and the yields 
obtained are: Corn, 45 to 50 bushels; oats, 25 to 40 bushels; 
barley, 30 to 35 bushels; and hay, iy 2 to 2 tons per acre. Pota¬ 
toes are grown on the type to a small extent for home use, but 
seldom on a commercial scale. The usual rotation consists of 
corn followed by a small grain, either oats or barley, or some¬ 
times by one year of each of these crops, and then by clover and 
timothy mixed, seeded with the grain, the field being cut for 
hay one or two years, before returning to corn. The stable 
manure is usually applied to the sod to be plowed under for the 
corn crops. The methods of cultivation, fertilization, and treat¬ 
ment are practically the same as those practiced on the Knox silt 
*For chemical composition and management see the discussion on 
composition of Knox silt loam on page 22. 
