IOWA ACADEMY OF SCIENCES. 
197 
developed valleys which have been cut down into the Des 
Moines stage of the Carboniferous. Nearly everywhere 
along the brow of the bluff are exposures of limestone of 
the Missourian stage. Sandstone of the Des Moines stage 
is found in the eastern part of the county. The hill slopes, 
and ridges lying near the larger streams are loess-covered; 
the prairies are covered with a dark, black loam. 
On the hills and clay ridges grow the white and black 
oaks, the ironwood and the hickory. The basswood and 
the bur oak flourish on the lower slopes; the ash, the elms, 
the buckeye, the walnuts, and the hard maple on the bot- 
toms. Along the river banks are found the box-elder and 
soft maple, the cottonwood and the willow. The hazel, the 
plum, the crab apple and the haw may be found every- 
where. 
In spite of the fact that the primeval forest is nearly 
exhausted, the timber area has increased to a considerable 
extent since the first advent of man in 1846. 
After the prairies were broken out no more fires swept 
over the country, keeping the timber confined to a narrow 
strip along the streams. Thus within the last forty years 
there has developed what is known as “second-growth’’ 
timber, which is found growing on the outskirts of the 
original timber area. 
At present not many large trees are left standing, and 
these are rapidly disappearing. Since the fencing is done 
almost entirely with wire, only fence posts are in demand. 
These posts are made principally from second-growth 
white and bur oak. Wood for fuel is still quite plentiful, 
yet it is diminishing at a rapid rate. 
What will be the outcome of the forest conditions of 
Madison and other counties of Iowa? Will the hills and 
valleys be stripped of the clothing nature intended they 
should have, or will man awake to his folly and cease 
destroying the forests without replacing them? This is a 
question worthy of intelligent consideration. The prob- 
lem of forests has been solved in some of the European 
countries, especially in Germany 
