§ 3. Abuse of agricultural land. The forces acting upon the land supply do not all work in the same direction. The land supply shrinks on some sides while it grows in others. The effects of bad husbandry are everywhere in the world apparent, and in many regions fertile fields have been physically and economically destroyed. In Asia, lands that once supported millions of people, perhaps tens of millions, are now deserts. Egypt, for a time reduced to a semi-desert condition, has only in the past century been restored to a certain extent by the use of new methods and a return to the old ones. Many of the areas that were the granaries of Rome can now hardly support a sparse, half-starving population. The land surface remains, but some of the elements indispensable to its value have been destroyed.

Even in young America may be seen the effect of a failure to keep land in repair. As the new rich lands of the West were opened up, the old lands in the East were allowed to wear out, and many of them were abandoned. Increasing returns marked the spread of the frontier westward. On the new lands in turn the same methods were followed, using up the first rich store of fertility with no attempt to keep up the quality of the soil. This may have been the best policy for the time; it would not have been economical to employ Old World methods of intensive husbandry when such rich extensive areas were being opened up. The resulting harvests were in many places phenomenal; in the valley of the James River in Dakota twenty crops of wheat were taken from the same lands with no apparent decrease, and in the black bottom lands of Indiana and Illinois, sometimes overflooded, enormous crops of corn have been raised still longer without fertilizer. But the process was one destructive in most places of the natural resources. As settlement moved westward, great forests fell in ashes, and the soil was robbed of the fertile elements which it had taken centuries for nature to store up. What was happening in America and in other new lands in the nineteenth century was the primitive method of exploitation of arable lands (Raubbau, robbery-tillage, as it is expressively called in German). In 1908 there were nearly 11,000,000 acres of abandoned farm lands in the United States and about 4,000,000 acres had suffered from soil erosion as the result of neglect.3

2 Report of National Conservation Commission (1909). Pub. Doc. Consecutive No. 5398, p. 67. Figures for 1908.

§ 4. Means of restoring lost fertility. In the older parts of the United States, as in the older countries, methods have long been employed to maintain the fertility of the soil by returning or increasing certain of the fertile elements. When by neglect of fields the underlying rocks have become denuded of their covering of organic materials, the process of restoration is most difficult, slow, and costly. The mountain sides have been stripped of forests, and the fertile soil has been washed into the river valleys in many of the older countries as in Greece and Italy, and in many parts of eastern and southern United States. Except in such cases, the soil is a self-replenishing agent, and if allowed to lie fallow, will slowly recover its fertility in whole or in part by disintegration of the subsoil, by slow wearing away of the infertile surface, and by plant action. But self-replenishing of soil is slow. It takes Nature about 500 years to create one inch of fertile top-soil. When the use of the land is needed, Nature's way is costly, for it costs time.

3 Report of the Conservation Commission, vol. 1, p. 78.

Other ways are quicker. Stable manures and garbage can be hauled from near-by towns; seaweed and mineral fertilizers, such as phosphates and lime, can be bought and applied. Subsoil plowing is practised to make available new layers of soil that are just as important as new acres added to the surface. Leguminous crops like peas and clover, which have the power of extracting nitrogen from the air, are cultivated, and either plowed under or fed to animals in the fields. If the roots of such plants are inoculated with bacteria their nitrogen-making power is greatly increased. The progress of science and of skill in agriculture is going far to maintain present food areas on the average in undiminished efficiency. In many respects the productivity of land may be even further increased. If we did not have to reckon on a great increase of population in the world, the problem of a continuing supply of land to grow food would be a relatively minor one.

§ 5. Land for products other than food. The problem of the supply of agricultural land is first, and most often, thought of in connection with the supply of staples like corn and wheat used for food. But it relates also to the supply of all other organic materials that have to be constantly produced, such as teas, coffee, spices, fruits, sugar, etc.; meats, fats, hides, bones, feathers, bristles, etc., from cattle, swine, sheep, or poultry; materials for textiles, as flax, linen, cotton, including those that must be obtained by the use of animals, as is the case with silk and wool; vegetable oils, as cottonseed, linseed, olive, and turpentine; animal oils, as lard, tallow; and thousands of other materials. Each of these kinds of goods has its own peculiar need of area and fertility, and its peculiar influences on the maintenance or exhaustion of the soil. Each must be separately studied, and thus has developed in each natural science its economic department - economic geology, industrial chemistry, economic botany, economic zoology and its more special branches, called economic entomology, economic ornithology, etc. In the case of many organic products the amount available promises to continue adequate for the needs of the future; in the case of others, scarcity makes itself much more quickly felt.

§ 6. Destruction of the natural forests. The forests have been used with less regard for future uses than have agricultural lands. Moreover, a conservative policy with regard to forests has been more tardily adopted, because the necessity of it was more tardily brought home to men. To the barbarians of Roman times, sparsely peopling the lands, and with few uses for timber, the primeval forests of Europe must have seemed as certainly renewable as the waters of the rivers or as inexhaustible a stock as the sand of the seashore. Left a century untouched by man, any land once naturally covered with trees would revert to a state like that of the primeval forest. Under the economic conditions of barbaric times the forests were self-replenishing sources of supply. They ceased to be so, in full measure, as population increased. The consequent curtailment of the rights of peasants to the free use of wood began to cause social and political troubles early in the Middle Ages. Until the eighteenth century scarcely any systematic beginning was made in the cultivation of the forest growth. Until a few generations ago in European countries, and until the present moment in most parts of America, timber has been cut with no attempt to maintain an undiminished stock.

Germany and France began in the eighteenth century to turn attention to systematic forest culture, but England, with exceptional transportation, could more cheaply get timber from Norway and from North America. The magnificent forests of America were a source of ready income to the settlers, affording immediately saleable exportable goods in the form of ship timber, masts, shingles, staves, pitch, and turpentine. A bountiful supply of lumber has always been a large element in the prosperity of the American people.

From the first settlement to the present, the use of the forests for lumber has speedily grown. To the settlers much of the forest was, however, a real hindrance to agriculture. "While great quantities of wood were used, still greater quantities were wasted, trees being girdled, the ground burned over, the timber destroyed in any way that would clear the soil - timber which to-day would be of far more value than is the cleared land on which it stood. Such methods met the immediate need, but considering present conditions, the labor was worse than thrown away.

Our forests once covered 45 per cent of the land area of the United States and even now they cover 25 per cent. The yearly growth of 12 cubic feet per acre equals less than one third of the annual consumption (40 cubic feet). "We take 260 cubic feet per capita, while Germany uses 37 cubic feet, and France 25 cubic feet."

The supplies of lumber must be sought on the very margins of our territory: Florida, Maine, northern Michigan and "Wisconsin, Washington, and Oregon, some of which supplies are so distant from the densely populated states as to be almost unavailable on account of the cost of transportation. Professor Marsh, as long ago as 1864, characterized the policy that had been thus far pursued: "We are breaking up the foundation timbers and the wainscoting of the house in which we live in order to boil our mess of pottage."

The indirect effects of these changes are fully as great as the direct ones. Forests greatly affect climate, temperature, and soil; they influence the humidity. They equalize the flow of streams, moderate the floods, and by preventing the washing down of the rich soil, keep the mountain sides from becoming bare and sterile rocks. So, near the end of the nineteenth century, the people in America began most tardily to think of forestry. Of our forests remaining, one fifth are still in public, and four fifths are in private ownership. The purpose of scientific forestry is to make forest lands permanent use-bearers, durative agents, to make them yield not a single crop of timber, but an unending series of crops.