Dry-Farming | Page 6

"sub-humid" and "humid" are used as above defined.
Precipitation over the dry-farm territory
Nearly one half of the United States receives 20 inches or less rainfall annually; and that when the strip receiving between 20 and 30 inches is added, the whole area directly subject to reclamation by irrigation or dry-farming is considerably more than one half (63 per cent) of the whole area of the United States.
Eighteen states are included in this area of low rainfall. The areas of these, as given by the Census of 1900, grouped according to the annual precipitation received, are shown below:--
Arid to Semi-arid Group Total Area Land Surface (Sq. Miles)
Arizona 112,920 California 156,172 Colorado 103,645 Idaho 84,290 Nevada 109,740 Utah 82,190 Wyoming 97,545 TOTAL 746,532
Semiarid to Sub-Humid Group
Montana 145,310 Nebraska 76,840 New Mexico 112,460 North Dakota 70,195 Oregon 94,560 South Dakota 76,850 Washington 66,880 TOTAL 653,095
Sub-Humid to Humid Group
Kansas 81,700 Minnesota 79,205 Oklahoma 38,830 Texas 262,290 TOTAL 462,025
GRAND TOTAL 1,861,652
The territory directly interested in the development of the methods of dry-farming forms 63 per cent of the whole of the continental United States, not including Alaska, and covers an area of 1,861,652 square miles, or 1,191,457,280 acres. If any excuse were needed for the lively interest taken in the subject of dry-farming, it is amply furnished by these figures showing the vast extent of the country interested in the reclamation of land by the methods of dry-farming. As will be shown below, nearly every other large country possesses similar immense areas under limited rainfall.
Of the one billion, one hundred and ninety-one million, four hundred and fifty-seven thousand, two hundred and eighty acres (1,191,457,280) representing the dry-farm territory of the United States, about 22 per cent, or a little more than one fifth, is sub-humid and receives between 20 and 30 inches of rainfall, annually; 61 per cent, or a little more than three fifths, is semiarid and receives between 10 and 20 inches, annually, and about 17 per cent, or a little less than one fifth, is arid and receives less than 10 inches of rainfall, annually.
These calculations are based upon the published average rainfall maps of the United States Weather Bureau. In the far West, and especially over the so-called "desert" regions, with their sparse population, meteorological stations are not numerous, nor is it easy to secure accurate data from them. It is strongly probable that as more stations are established, it will be found that the area receiving less than 10 inches of rainfall annually is considerably smaller than above estimated. In fact, the United States Reclamation Service states that there are only 70,000,000 acres of desert-like land; that is, land which does not naturally support plants suitable for forage. This area is about one third of the lands which, so far as known, at present receive less than 10 inches of rainfall, or only about 6 per cent of the total dry-farming territory.
In any case, the semiarid area is at present most vitally interested in dry-farming. The sub-humid area need seldom suffer from drouth, if ordinary well-known methods are employed; the arid area, receiving less than 10 inches of rainfall, in all probability, can be reclaimed without irrigation only by the development of more suitable. methods than are known to-day. The semiarid area, which is the special consideration of present-day dry-farming represents an area of over 725,000,000 acres of land. Moreover, it must be remarked that the full certainty of crops in the sub-humid regions will come only with the adoption of dry-farming methods; and that results already obtained on the edge of the "deserts" lead to the belief that a large portion of the area receiving less than 10 inches of rainfall, annually, will ultimately be reclaimed without irrigation.
Naturally, not the whole of the vast area just discussed could be brought under cultivation, even under the most favorable conditions of rainfall. A very large portion of the territory in question is mountainous and often of so rugged a nature that to farm it would be an impossibility. It must not be forgotten, however, that some of the best dry-farm lands of the West are found in the small mountain valleys, which usually are pockets of most fertile soil, under a good supply of rainfall. The foothills of the mountains are almost invariably excellent dry-farm lands. Newell estimates that 195,000,000 acres of land in the arid to sub-humid sections are covered with a more or less dense growth of timber. This timbered area roughly represents the mountainous and therefore the nonarable portions of land. The same authority estimates that the desert-like lands cover an area of 70,000,000 acres. Making the most liberal estimates for mountainous and desert-like lands, at least one half of the whole area, or about 600,000,000 acres, is arable land which by proper methods may be reclaimed for agricultural