The conservation of natural resources, the creation of new ones is a
topic which combines the qualities of science, service and utility.

Of all our resources the soil is the most vital. Most of the others have
some possibility of substitution, but for the soil there is no
substitute. The forest burned to destruction can rise again if the soil
remains. Some examination will show that the most vital part of the
whole conservation matter is the preservation of the soil, and that
soil conservation is 99 per cent the prevention of erosion. Soil robbery
by unscientific agriculture can go to its most extreme lengths and
reduce the soil to the depths of non-productivity; but scientific
agriculture can, by the addition of humus and some fertilizer, soon
restore such soil to high fertility. In these conditions of exhaustion
the loss to fertility by soil leaching is small, because of the
non-soluble character of the earth particles. Thus experiments at
Cornell have shown that in the average foot of top soil from rather
unproductive farms in a low state of production, there was plant food
sufficient for 6,000 crops of corn. We have all seen a single thunder
shower remove from a hillside corn field the fertility adequate for the
making of a hundred crops of corn.

American agriculture is peculiarly soil destructive. Three of our
greatest money crops--corn, cotton and tobacco--require that the earth
shall, throughout the summer, be loose and even furrowed with the
cultivator, which prepares the ground for washing away, and by its
furrow starts the gully. The second factor in this peculiarly
destructive agriculture is the fact of our emphasis of rainfall in
summer. Third in the list of factors of destruction is the rainfall
unit, the thunder shower, which dumps water, hundreds of tons per hour