FARMING WITHOUT IRRIGATION.
The general rule that agriculture in Utah is dependent on artificial irrigation finds exception in two ways. First, there are some localities naturally irrigated; and, second, there is at least one locality of which the local climate permits dry farming.
Along the low banks of many streams there are fertile strips of land. The soil is in every such case of a porous nature, and water from the stream percolates laterally and rises to the roots of the plants. Nearly all such lands are flooded in spring time, and they are usually devoted to hay as an exclusive crop; but some of them are above ordinary floods and are suited for other uses. It rarely happens, however, that they are farmed without some irrigation, for the reason that the use of the convenient water render the harvest more secure and abundant.
The same fertility is sometimes induced by subterranean waters which have no connection with surface streams. In such cases there is usually, and perhaps always, an impervious subsoil which retains percolating water near the surface. A remarkable instance of this sort is known at the western base of the Wasatch Mountains. A strip of land from 20 to 40 rods broad, and marking the junction of the mountain slope with the plain, has been found productive from Hampton’s Bridge to Brigham City, a distance of 18 miles. In some parts it has been irrigated, with the result of doubling or trebling the yield, but where water has not been obtained, the farmer has nevertheless succeeded in extracting a living. A similar but narrower belt of land lies at the eastern base of the Promontory range, and a few others have been found. In each locality the proximity of subterranean water to the surface is shown by the success of shallow wells, and there is evidently a natural irrigation.
There is one region, however, where natural irrigation is out of the question, but where crops have nevertheless been secured. Bear River “City” was founded by a company of Danes, who brought the water of the Malade River to irrigate their fields. After repeated experiment they became satisfied that the water was so brackish as to be injurious instead of beneficial, and ceased to use it; and for a number of years they have obtained a meagre subsistence by dry farming. A district lying south of Ogden and east of Great Salt Lake, and known as “the Sand Ridge”, has recently been brought in use, and in 1876 and 1877 winter wheat was harvested with a yield variously reported as from 10 to 15 bushels per acre. This success is regarded by some of the older settlers as temporary and delusive, for it is said to have depended on exceptional spring rains; but the majority of the community have faith in its permanence, and the experiment is being pushed in many valleys. In Bear River City and on the Sand Ridge water is not found by shallow wells, and the land is naturally dry. In these localities, and, so far as I am aware, in all others where dry land has been successfully farmed, the soil is sandy, and this appears to be an essential condition. Success has moreover been restricted to the line of valleys which lie at the western base of the Wasatch Mountains and near Great Salt Lake.
This last feature depends, as I conceive, on a local peculiarity of climate. The general movement of the atmosphere is from west to east, and the air which crosses the lake is immediately lifted from its level to the crest of the Wasatch. Having acquired from the lake an addition to its quota of moisture, it has less power of absorption and a greater tendency to precipitation than the atmosphere in general, and it confers on the eastern shore of the lake a climate of exceptional humidity.
The character of this climate is clearly indicated by the assemblage of the observed facts in regard to precipitation. Through the kindness of Prof. Joseph Henry I have been permitted to examine the rain records accumulated by the Smithsonian Institution, including not only those which have been embodied in the published “Tables,” but the more recent data to be included in the forthcoming second edition. The following table shows the mean annual precipitation for all stations in Utah, Nevada, Wyoming, and Colorado, which have a record two years or more in extent, together with certain other facts for comparison. The temperature means are taken from the Smithsonian Temperature Tables and the United States Signal Service Reports.
| Station. | Annual precipitation. | Mean Temperature. | Height above sea. | Latitude. | Length of record. | |
|---|---|---|---|---|---|---|
| Spring. | Summer. | |||||
| Inches. | Deg. F. | Deg. F. | Feet. | ° ´ | Yrs. Mos. | |
| Salt Lake City, Utah | 24.81 | 50 | 74 | 4,354 | 40 46 | 9 2 |
| Camp Douglas, Utah | 18.82 | 49 | 73 | 5,024 | 40 46 | 10 3 |
| Colorado Springs, Colo | 17.59 | 44 | 68 | 5,970 | 38 49 | 3 0 |
| Camp Winfield Scott, Nev | 17.33 | 47 | 74 | — | 41 34 | 2 8 |
| Fort Massachusetts, Colo | 17.23 | — | — | 8,365 | 37 32 | 5 1 |
| Golden City, Colo | 17.01 | — | 72 | 5,240 | 39 44 | 2 3 |
| Fort Sedgwick, Colo | 15.44 | 47 | 74 | 3,600 | 40 58 | 2 1 |
| Fort Fred. Steele, Wyo | 15.38 | 41 | 66 | 6,845 | 41 47 | 5 5 |
| Fort Fetterman, Wyo | 15.10 | 41 | 67 | 5,012 | 42 50 | 5 7 |
| Fort Garland, Colo | 14.86 | 43 | 64 | 7,864 | 37 25 | 13 1 |
| Fort Laramie, Wyo | 14.45 | 47 | 73 | 4,472 | 42 12 | 17 8 |
| Fort D. A, Russell, Wyo | 14.09 | 36 | 64 | 6,000 | 41 12 | 5 1 |
| Denver, Colo | 13.77 | 46 | 69 | 5,250 | 39 45 | 5 1 |
| Harrisburg, Utah | 13.74 | — | — | 3,275 | 37 10 | 2 2 |
| Fort Reynolds, Colo | 13.26 | 52 | 75 | 4,300 | 38 12 | 2 8 |
| Fort Lyon, Colo | 12.56 | 51 | 77 | 4,000 | 38 08 | 7 9 |
| Fort Sanders, Wyo | 11.46 | 38 | 62 | 7,161 | 41 17 | 6 10 |
| Saint George, Utah | 11.39 | — | — | 2,800 | 37 13 | 2 11 |
| Camp Halleck, Nev | 10.98 | 45 | 68 | 5,790 | 40 49 | 5 8 |
| Cheyenne, Wyo | 10.14 | 40 | 66 | 6,075 | 41 08 | 3 9 |
| Camp McDermitt, Nev | 8.53 | 46 | 70 | 4,700 | 41 58 | 6 4 |
| Fort Bridger, Wyo | 8.43 | 39 | 63 | 6,656 | 41 20 | 12 10 |
| Fort Churchill, Nev | 7.43 | 52 | 75 | 4,284 | 39 17 | 3 9 |
| Camp Floyd, Utah | 7.33 | 49 | 74 | 4,867 | 40 16 | 2 6 |
| Means | 13.80 | 45 | 70 | 5,300 | 40 05 | — |
Two of the stations, Salt Lake City and Camp Douglas, lie within the zone of climate modified by Great Salt Lake, and a brief inspection of the table will show how greatly their climate is influenced. As a general rule, the localities of greatest precipitation in the Rocky Mountain Region have so great altitude that their summer temperature does not permit agriculture, but Salt Lake City, with an altitude 1,000 feet below the average of the 24 stations, and a temperature 4° above the average, has a rainfall 11 inches greater than the average; and Camp Douglas, 3° warmer than the average and 250 feet lower, has a rainfall 5 inches greater. If the two stations are compared with those which lie nearest them, the contrast is still more striking. Camp Halleck, 130 miles west of the lake, and 600 feet higher than Camp Douglas, has a rainfall of 11 inches only. Fort Bridger, 90 miles east of the lake and 1,600 feet higher than Camp Douglas, has a rainfall of 8 inches. Camp Floyd, 30 miles south of the lake and sheltered from its influence by mountains, receives only 7¹⁄₃ inches. But Salt Lake City and Camp Douglas, lying between the lake and the Wasatch Range, record respectively 24.8 and 18.8 inches.
In fine, it appears that the climate of the eastern shore of Great Salt Lake is decidedly exceptional and approximates in humidity to that of Central Kansas. The fact that it admits of dry farming gives no warrant for the belief that large areas in the Arid Region can be cultivated without irrigation, but serves rather to confirm the conclusion that the limit to remunerative dry farming is practically drawn by the isohyetal line of 22 inches. Even in this most favored district the yield is so small that it can be doubled by irrigation, and eventually water ditches will be carried to nearly all the land that has yet been plowed.