80 BIG SPRING PRAIRIE. 
The area just south of the new road, No. 1, marked 
W. B. (wooded bay) was formerly a bay of the old lake. 
The silt carried down from one of the drainage valleys 
gradually helped to fill this up. In time, it passed 
through successive stages until it became eventually 
well wooded. The woods was cleared off, and the area 
was brought under cultivation. At a depth of i0 or 12 
inches there is a flaky sort of soil, which burns with a 
bright blaze similar to cannel coal ‘The extent of this 
deposit was not ascertained, but most probably is quite 
limited in thickness and extent. The texture of this 
soil is n:uch firmerethan the muck on other portions of 
prairie, and loses less in weight and volume on drying 
than the muck from other portions of prairie. The loss 
in burning is considerable, but was not tested 
quantitatively. 
The northeast corner of woods K of map II, was 
formerly a small bay into which one of the drainage 
valleys emptied. After it became filled up with silt 
and plant remains, a marsh condition arose; and such 
plants as Iris and Spathyema made their appearance. 
These plants still survive in the woods in spite of the 
rather thorough drainage. In this bay there was a 
gradual slope of the clay bank tothe northeast; and 
after first ditch was dug, seedling elms and ash sprang 
up in the muck soil, as now there was moving water in 
the soil instead of stagnant water. The roots extended 
through the muck and into the clay sub-soil. As the 
soil settled after drainge, the roots became considerably 
exposed as represented in figure 2and 3. After the 
settling of the soil, some of the trees were blown down 
as the roots did not furnish sufficient support to resist 
wind action. Many of the trees are leaning’ more or 
less and as some of the exposed roots are gradually de- 
caying, many more will succumb in the near future, 
and a forest suited to the new conditions will gradually 
supplant it if leit in a state of nature. 
