66 



Summary of results of duti/ of tvdter experiineiiis on field crops in Gallatin Count;/, in LS99. 



Crop. 



Clover 



Peas.. 



Grain. 



Barley 



Oats . . 



Do 



Do 



Do 



Area 

 irrigated. 



Acres. 



27.44 



4.23 



11.27 



66.39 



23.41 



7.26 



2.48 



25.09 



Yield per acre. 



3 tons 



31.'-'.'i1his1h'1s 

 riT.H'J husliols 

 73 t»u>licls .. 

 .'il l)Uslu'ls . . 

 72.75 blisht'ls 

 72.75 bushels 



Depth 

 applied. 



Feet. 

 1.02 

 1.10 

 1.98 

 .98 

 1.53 

 1.34 

 2.16 

 1.28 



MEASURExMENTS MADE IN 1900. ' 



The measurements made in 11)00 to determine the dut}' of water on 

 individual fields were not confined to the Gallatin Valley, but were 

 extended to the Bitter Hoot and Yellowstone valleys." The crops 

 tested in the Gallatin Valley were grain and red clover. Water was 

 first used June 1 and its use was continued until August 11. The 

 clover crops were irrigated from two to four times and the grain cro})s 

 were each irrigated twice. The former received on an average 18 

 inches in depth, of which 1 inches was rain; the latter received 26.5 

 inches, of which nearly 5 inches was rain. 



The quantity of water applied to three fields belonging to the Bitter 

 Root stock farm of Ravalli County was determined. The first of these 

 consisted of a 10-acre tract of 5-year-old orchard trees. A light veg-. 

 etable loam formed the top soil, with a subsoil of gravel and small 

 cobljles. Light irrigations were applied in April, June, July, and 

 August, l)ut the aggregate of the four with the rainfall was only is 

 inches in depth over the surface. The quantitv of water applied in 

 two irrigations to a large field of oats on the same stock farm was 17 

 inches. 



The third experiment was made on a high gravelly bench traversed 

 by numerous ravines, and much of the water used was apparently 

 wasted. The yield of oats averaged 81 bushels, and yet the volume 

 applied in two irrigations would have covered the tract of 102.2 acres 

 to a depth of 6 feet. 



In Yellowstone County the amount of water used on a field of alfalfa 

 comprising 53.1 acres was measured. Three crops were grown with 

 only one heavy irrigation. The jdeld per acre for the season was 5.17 

 tons, and the depth of water applied was 16 inches. This practice of 

 raising so many crops with one application of water is not representa- 

 tive of this alfalfa-raising district. Many raise four crops in one sea- 

 son, and water the land for each crop. In doing so each irrigation 



aU. S. Dept. Agr., Office of Experiment Stations Bui. 104, pp. 267-292. 



