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UNIV. OF MICH.
Issued January 22, 1909
U. S. DEPARTMENT OF AGRICULTURE,
FOREST SERVICE-Circular 159.
GIFFORD PINCHOT, Forester.
THE FUTURE USE OF LAND IN THE UNITED STATES.
CHIEF, OFFICE OF SILVICS.
WASHINGTON: GOVERNMENT PRINTING OFFICE: 1909
Land as a natural resource..
FIG. 1. Probable future land classification of North America
THE FUTURE USE OF LAND IN THE UNITED STATES.
In the last analysis all material wealth, all the comforts and necessities of life, are the product of two elements-nature and labor. It may be truly said that nature, or the earth, is the mother and labor the father of all products necessary to sustain human life. The richness and prosperity of a country, therefore, depend on the presence of natural resources within its borders, such as water, minerals, forests, and cultivable soils on the one hand, and intelligent human energy on the other to shape them into the forms necessary for the needs of man. Of the two elements the natural resources are indispensable, for in a country like the Desert of Sahara all human effort would be of but little avail. The growth of a nation depends, therefore, upon the extent of the natural resources and upon the knowledge of how to use them with as little destruction as possible.
The resources of a country fall naturally into three groups-water, minerals, and land-which represent, respectively, resources which are inexhaustible, resources which are exhaustible and can not be renewed, and resources which are exhaustible but can be renewed.
It may be questioned, indeed, whether there is such a thing as an inexhaustible natural resource. Even water, through the denudation of the drainage basins, may become irregular in its flow, or through the careless disposal of refuse may become polluted so that it can not be used. Mines are illustrations of resources which are exhaustible and not renewable. Gas, oil, coal, and iron once gone are gone forever. Of all the natural resources the only one which contains within itself the possibility of infinite renewal is land. The nation should therefore be most vitally concerned with the conservation and improvement of this resource. Human control over such natural resources as minerals is limited. The only possible means of conservation is the avoidance of waste, but their ultimate exhaustion is unavoidable. With agricultural and forest land, however, it is otherwise. Land can not only be conserved, but constantly improved and its yield increased. While in England the iron ores and the coal are becoming constantly harder to get and their exhaustion is threatened, the agricultural land, after a thousand years of cultivation, is now more productive than ever. The wheat fields of England under intensive cultivation yield 30 bushels to the acre, while the virgin fields of America on an average yield less than 13.
If a farsighted national policy in the conservation of natural resources is to make provision for an ever-increasing population, then the greatest possibilities lie in the direction of developing the
land in all its forms-field, forest, and range-for, notwithstanding all possible economy in the use of the nonrenewable resources, they are bound to decrease as time goes on. Nor will they be able to give employment to the increasing population. Only in the development of the renewable resources lies an infinite field for the support and employment of a growing population.
LAND AS A NATURAL RESOURCE.
In a new country, with a wealth of land and a scanty population, the use to which the land is first put can not serve as an indication of its best ultimate use. Gradually, as the population increases and the knowledge of the properties of the different classes of land grows, there is a closer correspondence between the character of the land and the crops to which it is devoted. In such densely populated countries as Belgium and France practically every acre of land is put to its most appropriate use. Thus in France, for instance, 83 per cent of the poorer sandstone soils is forested, while of the fertile alluvial soils only 5 per cent is under forest. More than half (56 per cent) of the French forests are on nonagricultural, calcareous soils. But in this country there are still thousands of acres naturally adapted to agriculture which are now under forest growth, chiefly hardwoods; and there are many slopes cleared of timber and turned into pastures or fields which in a few years become washed out and had best be kept under forest cover.
How rapidly the relative areas of land devoted to the different purposes are changing may be seen from this. Hardly one hundred years ago the United States east of the Mississippi River was an almost unbroken forest, comprising something over 1,000,000 square miles, or about 700,000,000 acres. Now, after about a century of settlement, there are not more than 300,000 square miles of merchantable forest land in the eastern United States. About 330,000 square miles have been cleared for farm land. The remainder has been culled of its valuable timber and devastated by fire or else turned into useless brush land. With the growth of population and the greater demand for agricultural land the ratio between farm and forest land will change still further. The forests will be more and more crowded into the mountains and upon soils too thin or too poor for agricultural purposes. It may be safely assumed that in fifty or one hundred years the proportion of land devoted to the different purposes will change almost as much as it has during the past century. These changes will occur especially in the eastern part of the United States, because there the forest is not confined, as it is in the West, to high altitudes, where agriculture is generally impracticable. In the West the forests, with a few exceptions, as in the low country around Puget Sound, are in the high mountains, which rise in the midst of semiarid plains, and their original area of 150,000 square miles, half of which lies in the Sierra Nevadas and in the Cascades and half in the Rockies, has
changed but very little since settlement. In the West the increase of agricultural land must be secured chiefly through the irrigation of the semiarid land.
If we take a long look ahead into the future and try to picture to ourselves what will be the ultimate proportion of farm, forest, range, and desert in this country fifty years from now, in the light of the
FIG. 1.-Probable future land classification of North America.
increasing demand for agricultural land and of an approximate knowledge of the climatic conditions and the physical properties of the different lands in this country, we shall get something like the condition shown in figure 1.