650 



THE IRRIGATION AGE. 



Experiments in Supplemental Irrigation 



With Small Water Supplies at 



Cheyenne, Wyo., in 1909. 



Barley. Plats 1 and 10 were seeded to Beardless Hull- 

 less barley, and the following shows the results : 



YIELDS OF IRRIGATED AND UNIRRIGATED BARLEY. 



The Office of Experiment Stations has maintained since 

 1905 at Cheyenne and Newcastle, Wyo., and Eads, Colo., ex- 

 perimental farms for the purpose of testing the value of irri- 

 gating small areas in connection with the farming of larger 

 areas without irrigation in the semi-arid region where water 

 for the irrigation of any large part of the arable land is not 

 available. The results at Cheyenne and Newcastle for the sea- 

 sons 1905 to 1908 have been published in Circular 92 of this 

 office. The present report gives the results at the Cheyenne 

 farm in 1909. This is the first season that satisfactory re- 

 sults have been secured. Heretofore the water system was 

 not in good working order, while destructive hailstorms, occur- 

 ring when crops were maturing, left no measure by which 

 to test the merits of the different systems used. 



Although the spring of 1909 was unusually late and the 

 planting of some crops was delayed, the crops were not greatly 

 retarded, and hailstorms did not seriously injure them. A 

 careful record of all operations and yields was kept by the 

 irrigation farmer in charge of the experiment work. 



Plat. Treatment. 



1 Irrigated 



10 Unirrigatcd . . 



Amount 

 Amount rainfall in 



water in inches, Yield, 



rpplied, Jan. 1 to in 



inches. Aug. 5.* bushels. 



6.C 11.39 42J4 



None. 11.S9 16J4 

 *Date harlev was harvtsted. 



Remarks. 

 Excellent grade. 



The accompanying map (fig. 1) shows the plats referred 

 to and will assist the reader in following the account of the 

 work. 



Full Irrigation v. No Irrigation. 



Plats 1, 2, 3, i and 5 were irrigated with what was con- 

 sidered sufficient water to produce the best results. Plats 6, 

 7, 8, 9 and 10 w.'re unirrigated. All the plats from 1 to 10 

 received the same seeding, tillage and treatment with the ex- 

 ception of water, and as far as could be judged, the character 

 of the soil in all plats was the same. The area of each 

 plat is practically 1 acre 



This shows a gain of 26 bushels to the acre in favor of 

 irrigation. 



Field peas. Plats 2 and 9 were seeded to field peas, but 

 when they were fairly above the ground a hailstorm damaged 

 them to such an extent that it was thought advisable to plow 

 the plats and seed to millet as a catch crop, and at the same 

 time prevent the growth of weeds and furnish some forage 

 for the horses. Water to the depth of 4.2 inches was applied 

 to plat 2 at a time when the crop required moisture. Sixty- 

 nine days after ceding there was taken from plat 2 2,944 

 pounds of very good millet hay. Plat 9 was harvested at the 

 same time and gave a return of 737 pounds, a gain of 2,207 

 pounds in favor of the irrigated plat. 



Alfalfa. Plats 3 and 8 were planted to alfalfa in 1908. 

 Two crops were token from each of these plats during the 

 season of 1909. The yield on plat 3, which received 10.8 

 inches of water from irrigation, was almost 5,000 pounds. 

 Plat 8 yielded 2,100 pounds, showing a difference of 2,900 

 pounds in favor of plat 3. Both plats 

 were damaged by a hailstorm in the 

 early stages of growth. It will be seen 

 from this that a larger amount of water 

 was used than on other crops, but to get 

 the greatest returns from alfalfa water 

 should be applied abundantly, and espe- 

 cially is this true if there is a porous, 

 gravelly subsoil. While it is true that 

 the roots have a natural tendency to 

 penetrate deeply, it is a mistake to de- 

 pend on this deep rooting alone for 

 moisture, as shown by the large in- 

 crease in yield on the irrigated plat. 

 Wheat. Plats 4 and 7 were planted 

 to Turkey Red winter wheat. Plat 4, 

 to which water was applied 7.38 inches 

 in depth, yielded 38J^ bushels of wheat, 

 weighing 59J/2 pounds to the bushel, 

 showing well-filled grain. From plat 7 

 no returns were made, all the plants 

 being completely winterkilled. Undoubt- 

 edly the cause of such complete failure 

 was the lack of moisture when needed. 

 In 1908 the experience with winter wheat 

 was the same. The irrigated acre yielded 

 33 bushels of prime wheat while the un- 

 irrigated failed as completely as it did 

 this year. These plats are illustrative of 

 what is called continuous cropping, and 

 the results seem to indicate that this 

 practice is a failure so far as winter 

 wheat is concerned. 



Potatoes. Plats 5 and 6 were 

 planted to potatoes. Plat 5, with an ap- 

 plication of S.57 inches of water, yielded 

 140 bushels of potatoes, all sizes, and of 

 excellent quality. Plat 6. which was un- 

 irrigated, yielded 63 bushels of potatoes, 

 all sizes, and of as good a quality as the 

 irrigated crop, the only difference being 

 in the yield, which was 77 bushels greater 

 on the irrigated plat. The wheat men- 

 tioned above as a failure in 1908 was 

 planted on plat 6, consequently the plat was followed during 

 the season, and this undoubtedly helped the unirrigated potato 

 crop. Scab made its appearance in both plats, being a little 

 more pronounced in plat 6, but nothing really serious. 



Summer Fallowing. 



Plats 11 to 18, inclusive, are in the part of the farm de- 

 voted to experiments in summer fallowing. 



Field peas. Plat 11 was fallowed during 1908 and seeded 

 to field peas in the spring of 1909, but. was so damaged by the 

 hailstorm referred to that it was reseeded to millet, which 

 gave a return of 1,980 pounds on an area of 0.97 acre. Plat 



