Dry-farming, however, is well established.  There are large areas, especially in Nevada, that receive less than ten inches of rainfall annually, and one of the leading problems before the dry-farmers of this district is the determination of the possibility of producing crops upon such lands without irrigation.  On the older dry-farms, which have existed in some cases from forty to fifty years, there are no signs of diminution of soil-fertility.  Undoubtedly, however, even under the conditions of extremely high fertility prevailing in the Great Basin, the time will soon come when the dry-farmer must make provision for restoring to the soil some of the fertility taken away by crops.  There are millions of acres in the Great Basin yet to be taken up and subjected to the will of the dry-farmer.

Colorado and Rio Grande River Basins

The Colorado and Rio Grande River Basins include Arizona and the western part of New Mexico.  The chief dry-farm crops of this dry district are wheat, corn, and beans.  Other crops have also been grown in small quantities and with some success.  The area suitable for dry-farming in this district has not yet been fully determined and, therefore, the Arizona and New Mexico stations are undertaking dry-farm surveys of their respective states.  In spite of the fact that Arizona is generally looked upon as one of the driest states of the Union, dry-farming is making considerable headway there.  In New Mexico, five sixths of all the homestead applications during the last year were for dry-farm lands; and, in fact, there are several prosperous communities in New Mexico which are subsisting almost wholly on dry-farming.  It is only fair to say, however, that dry-farming is not yet well established in this district, but that the prospects are that the application of scientific principles will soon make it possible to produce profitable crops without irrigation in large parts of the Colorado and Rio Grande River Basins.

The mountain states

This district includes a part of Montana, nearly the whole of Wyoming and Colorado, and part of eastern Idaho.  It is located along the backbone of the Rocky Mountains.  The farms are located chiefly in valleys and on large rolling table-lands.  The chief dry-farm crop is wheat, though the other crops which are grown elsewhere on dry-farms may be grown here also.  In Montana there is a very large area of land which has been demonstrated to be well adapted for dry-farm purposes.  In Wyoming, especially on the eastern as well as on the far western side, dry-farming has been shown to be successful, but the area covered at the present time is comparatively small.  In Idaho, dry-farming is fairly well established.  In Colorado, likewise, the practice is very well established and the area is tolerably large.  All in all, throughout the mountain states dry-farming may be said to be well established, though there is a great opportunity for the extension of the practice.  The sparse population of the western states naturally makes it impossible for more than a small fraction of the land to be properly cultivated.