580 Plain, Prairie, and Forest. [ October, 
The writer has no theory to put forward on the subject ; he 
has simply gone on for years observing the facts, and it is a very | 
brief résumé of these facts which it is here proposed to give. | 
But he will first endeavor to dispose of some of the theories of 
others, declaring that he believes himself to have had better op- 
portunities for observing in the prairie region than any of the 
writers who of late years have taken up this subject. ; 
There seem to be two prominent theories before the public 
for their choice in accounting for the existence of the prairies. 
One of these may be very shortly disposed of, since it is so at 
variance with all the facts that, as Mr. Foster observes,’ it is 
“ worthy only of a passing notice.” It is to the effect that the 
prairies exist because the trees have been burned off by the In- 
dians! To use the words of Mr. St. John, formerly State Geolo- 
gist of Iowa, and one of the most zealous upholders of this 
theory, “ The real cause of the present existence of the prairies 
is the prevalence of the annual fires. If these had been prevented 
fifty years ago, Iowa would now be a timbered instead of a 
prairie State.” There seem to be some Western men who are 
not content unless they can make their country ‘out to be not 
only the garden but the arboretum of the world. The trees are 
wanting at present over extensive areas; but they must once 
have existed, otherwise the Mississippi Valley would be or have 
been deficient in one of those attributes by which an ideally per- 
fect country is characterized. As the trees do not now exist, 
they must have been destroyed, and, no other agent being at 
hand so destructive as fire, that is had recourse to. The prairie 
grass frequently gets on fire; these fires have burned up the 
trees! Why the same conditions do not hold good on the pres 
ent forest-covered States has never been explained. Why the 
fires have spread themselves only on comparatively level ground, 
and spared the mounds and the bluffy sides of the rivers, is a180 
a mystery; equally so why they have avoided certain tre 
quite surrounded by prairie, like the “ groves” of Wisconsin; 
and, furthermore, why they have paid such respect to the differ- 
ences of soils and other geological conditions. We have see? 
large areas of forest burned over, both in New England and on 
Lake Superior, as well as in the Rocky Mountains, but have no 
recollection of any of these areas having become prairies mo 
sequence. Once a forest, always a forest, so far as our experienc? 
puerile.” 
1 The Mississippi Valley, page 76. Dr. Newberry says the idea is “ simply 
(Geology of Ohio, i,.30.) 
