Pg 120

          It is estimated that seven eighths of the surface of the State was prairie when first settled. They are not confined to level surfaces, nor to any particular variety of soil, for within the State they rest upon all formations, from those of the Azoic to those of the Cretaceous age, inclusive. Whatever may have been their origin, their present existence in Iowa is not due to the influence of climate, nor the soil, nor any of the underlying formations. The real cause is the prevalence of the annual fires. If these had been prevented fifty years ago, Iowa would now be a timbered country. The encroachment of forest trees upon the prairie farms as soon as the bordering woodland is protected from the annual prairie fires, is well known to farmers throughout the State.

          The soil of Iowa is justly famous for its fertility, and there is probably no equal area of the earth’s surface that contains so little untillable land, or whose soil has so high an average of fertility. Ninety-five per cent of its surface is tillable land.