12 
BULLETIX 498, U. S. DEPARTMENT OF AGRICULTURE. 
every fifth plat sown uniformly to one variety and regarded as a 
check. The two methods described in previous publications 1 have 
been used to determine relative or computed yields, but neither has 
proved entirely satisfactory. The variation in check-plat yields of 
spring grains usually has not been great. Occasionally, however, 
wide variations occur in the yields of check plats which can not be 
explained in any satisfactory manner. 
Fig. 6.— A bar weeder, or "slicker," in operation at the Eastern Oregon Dry-Farming Substation. 
Beginning with 1913, each variety of spring grain in a varietal test 
has been sown in duplicate twentieth-acre plats. The plats in the 
two series are arranged as follows : 
1 
11 
2 
12 
3 
13 
4 
14 
5 
15 
6 
16 
17 
8 
18 
9 

19 
J 
20 
11 
1 
12 
2 
13 
3 
14 
4 
15 
5 
16 
6 
17 
7 
IS 
8 
19 
9 
20 
10 
All yields in this bulletin are reported in bushels per acre, based on 
the actual yields of a single tenth-acre or the average actual yields of 
two twentieth-acre plats. 
TREATMENT OF PLATS. 
The general practice in growing cereals in the Columbia Basin is to 
alternate a grain crop with bare fallow, commonly called summer 
1 Cardon, P. V. Cereal investigations at the Nephi substation. U. S. Dept. Agr. Bui. 30, p. 12, 33. 
1913. Clark, J. Allen. Cereal experiments at Dickinson, N. Dak. U. S. Dept. Agr. Bui. 33, p. 11, 12. 
1914. 
