6 BULLETIN" 546, U. S. DEPARTMENT OF AGRICULTURE. 



differences in the yields of the crops on the several plats would be 

 associable with soil-moisture differences in the spring, as the only 

 variation in the treatment of the land was the irrigation applied to 

 half the plats in the fall of each year. 



CROP YIELDS. 



Two plats of each of the seven crops were grown each year on the 

 fall-irrigated land, and the same number were grown on check series, 

 the latter receiving no fall irrigation. The yields are reported in 

 detail in Table III. 



Table III. — Yields of crops in the fall-irrigation experiments at the Belle Fourche Experi- 

 ment Farm in 1914, 1915, and 1916. 



Plats and year. 



Series. 



Wheat. 



Oats. 



• 

 Barley. 



Flax. 



Corn. 



Beets. 



Potatoes. 



Fall-irrigated plats: 

 1914 



{ 

 { 

 { 



II 

 IV 

 II 



IV 



II 



IV 



Bushels. 

 31.5 

 28.5 

 24.0 

 19.3 

 15.5 

 13.8 



Bushels. 

 47.8 

 39.0 

 70.9 

 60.6 

 80.6 

 72.2 



Bushels. 

 29.1 

 26.8 

 35.7 

 34.8 

 39.2 

 38.3 



Bushels. 

 17.0 

 10.5 

 18.8 

 16.3 

 10.4 

 9.1 



Bushels. 

 53.4 

 45.8 

 29.3 

 29.0 

 50.4 

 45.4 



Tons. 

 8.9 

 7.3 

 5.1 

 3.6 

 13.2 

 12.2 



Bushels. 

 172 



1915 



127 

 108 



1916 



77 

 267 





254 



Average, three 



22.1 



61.9 



33.9 



13.7 



42.2 



8.4 



167 





{ 



{ 



I 

 III 



I 

 III 



I 

 III 





Check plats: 



1914 



24.6 

 19.3 

 22.7 

 24.5 

 14.3 

 15.3 



40.0 



47.8 

 80.0 

 80.3 

 73.9 

 84.7 



28.7 

 26.0 

 43.2 

 33.5 

 41.8 

 43.6 



17.4 

 14.8 

 16.3 

 19.1 

 12.1 

 11.8 



47.2 

 51.4 

 29.3 

 33.7 

 47.9 

 53.9 



9.5 

 7.1 

 5.9 

 5.7 

 13.5 

 13.9 



173 



1915 



158 

 105 



1916 



100 

 225 





272 



Average, three 



20.1 



67.8 



36.1 



15.2 



43.9 



9.2 



172 









In order to facilitate comparisons of the yields shown in Table III, 

 the figures have been calculated in percentages, and the relative yields 

 are shown in Table IV, in which the yields of the check plats are repre- 

 sented as 100 per cent. The yield shown for each crop is the average 

 of duplicate plats. 



^Table IV. — Relative yields (expressed in percentages) of crops in the fall-irrigation experi- 

 ments at the Belle Fourche Experiment Farm in 1914, 1915, and 1916. 



L.' 



1914 





1915 







1916 





3-year average. 









CO t 







s 







CO < 







CO -A 





-3 





Sfc 



■o 







-3 





oh 



■6 





IS 



Crop. 



C3 





- — 



C3 

 60 





-1 



Kb 





OcJfi 



o 

 So 







E 



M 



•« o 



£ 



M 



M 



3 



M 



— c 



^ 



M 



— 3 





_ 



o 



.5 >-"3 



^ 





ftfi 





o 



.9 ^ « 





o 



.9 >>■£ 





"3 



r^ 



ci— t/. 



a 



^ 



o"^ 



"5 



si 



rt^ctf 



S3 



,q 



C9-2 OB 





a 



o 



o 



Ph 



o 



- 8 

 -18 



- 8 



- 1 



- 6 

 -26 

 -10 



98 

 96 

 91 

 88 

 94 

 93 

 105 



O 



o 



fe 



O 



o 



Wheat 



137 

 99 

 102 



8.-, 

 101 

 98 

 90 



100 

 100 

 100 

 100 

 100 

 100 

 100 



+ 37 



- 1 

 + 2 

 -15 

 + 1 



- 2 

 -10 



92 

 82 

 92 

 99 

 94 

 74 

 90 



100 

 100 

 100 

 100 

 100 

 100 

 100 



100 

 100 

 100 

 100 

 100 

 100 

 100 



- 2 



- 4 



- 9 

 -12 



- 6 



- 7 

 + 5 



110 

 91 

 94 

 90 

 96 

 91 

 97 



100 

 100 

 100 

 100 

 100 

 100 

 100 



+ 10 



Oats 



- 9 





- 6 



Flax 



-10 





- 4 





- 9 





— 3 









102 



100 



+ 2 



89 



100 



-11 



95 



100 



— 5 



96 



100 



— 4 







