58 BULLETIN 1178, U. S. DEPARTMENT OF AGRICULTURE. 
In 1917 this experiment was repeated, except that the wheat was 
sown 1n rows 4, 6, 8, and 12 inches apart and two varieties were used. 
The yields of grain of Kharkof and of Pacific Bluestem in pounds per 
plat are shown in Table 44. 
TABLE 44.— Yields of Kharkof winter wheat and Pacific Bluestem spring wheat when 
sown at three different rates and at four different distances between rows at Moro, Oreg., 
an 1917. 
| Yields per plat (pounds). 
\ apes eer of ginch spacing. | 6-inch spacing. | 8-inch spacing. 12-inch spacing. 
| r 
Series 1. | Series 2. | Series 1. | Series 2. | Series 1. | Series 2. | Series 1. | Series 2. 
Kharkof: 
A DECKS. 2% as ones ae 8.0 8.0 8.5 6.0 6.0 8.0 7.0 9.0 
Dp pecks.2 =. -2=..5- GO 8.0 | 7.0 7.0 | 5.0 6.5 7.0 6.0 
GxpeckS-5.-- bk. 6.0 9.0 5.0 8.0 | 4.0 8.5 5.0 6.5 
Average........ Tel 6.9 | 6.3 627 
Pacifie Bluestem: | | | 
4 pecks........--- 3.0 4.0 | 4.0 | 3.5 2.0 | 3.5 2.0 3.0: 
Rpecks. 0-26. = 4.0 4.5 | 3.5 | 4.5 | 3.5 4.0 3.0 4.0 
G@peckss 2 ee: 3.0 4.0) 4.5 | 4.0 3.5 4.5 2.0 4.0 
Average...... Gi 3.8 | 4.0 3.5 3.0 
In 1916 the highest yields were obtained from the 4-inch and 6-inch 
spacings with Pacific Bluestem wheat, as is shown in Table 43. In 
1917 shghtly higher yields of Kharkof wheat were obtained from the 
4-inch spacing, with the yields from the 6, 8, and 12 inch spacings 
Serenade identical, as is shown in Table 44. There also was not a 
wide variation in the yields obtained in 1917 from the Pacific Bluestem 
sown with the 4, 6, 8, and 12 inch spacings. The 12-inch spacing 
gave the lowest yield and the 6-inch spacing the highest, as is also 
shown in Table 44. 
SUMMARY. 
Wheat is one of the most important farm crops grown in Wash- 
ington, Oregon, Idaho, and Utah and is the only important commer- 
cial crop grown on their nonirrigated lands. Successful dry-farm 
wheat production in these States is based on alternate years of crop 
and clean fallow. 
Experiments to determine the effect of different tillage methods 
on the yield of wheat were begun at Nephi, Utah, in 1904, at Moro, 
Oreg., in 1911, and at Lind, Wash., in 1916, by the agricultural 
experiment stations of these States in cooperation with the United 
States Department of Agriculture. 
The altitude at Moro is 1,800 feet, and the soil type is silt loam. 
The altitude at Lind is 1,600 feet and the soil a fine sandy loam. 
The altitude at Nephi is nearly 6,000 feet and the soil a heavy clay 
loam. 
The average annual precipitation at Moro is 11.52 inches; at Lind, 
7.22 inches; and at Nephi, 13.27 inches. 
The average evaporation from a free water surface at Moro in the 
7-month period, April to October, inclusive, was 44.88 inches; at 
Nephi, 48.37 inches. No evaporation records were kept at Lind, but 
other weather data indicate that the evaporation is as great as if not 
ereater than at Moro. . 
