8 4 
Journal of Agricultural Research 
Vol. XXVII, No. 2 
The use of the small plats, containing approximately 0.0029 of an acre, 
made it possible to have a large number of replications of each strain. 
Twelve of these replications were distributed in alternate rows across one 
series and 10 were distributed lengthwise of the experiment. The strain 
occurring in alternate rows in any one series served as a check on soil 
variation within that unit and the strains as a whole distributed length¬ 
wise of the field served as controls on differences between the series. 
Looked at in this way, therefore, there were alternate check plats through¬ 
out the experiment without any increase being required in total area. 
Moreover, each strain competed with every other strain the same number 
of times. 
Table; II. —The mean actual and adjusted yields and the average values of the correspond¬ 
ing yrow plats of 11 strains of corn compared at Burdette, Ark., in IQ2I 
Average of 22 replications.® 
Strain 
No. 
Designation. 
Adjusted yields, basis of— 
Aver¬ 
age of 
3-row 
plats. 
Actual yields. 
2-alternate- 
row plats. 
3-row plats. 
I 
2 
Pounds. 
3 
I 
| 
1 Btishels. 
| 4 
Bushels. 
5 
Bushels. 
6 
Per 
cent. 
7 
I 
Whatley Prolific. 
12.7 
73.48i1.50 
72.61 ii. 21 
72.66io. 76 
101.21 
2 
St. Charles White. 
11.1 
64.22i1.45 
63.99 ± .98 
63 •96 i -73 
100.88 
3 
St. Charles White X 
Whatley, Fj. 
12.5 
72.32i1.45 
73 - 2 5 ± -98 
72.85i .67 
99.18 
4 
Whatley X St. 
Charles White, F^. 
”•5 
1 
1 
| 72.32i2.43 
72.9Oil.56 
7 2 - 45 ± -99 
99 - 3 2 
5 
Selection No. 201 F 2 . . 
11.2 
64.80 i 1.62 
67.8l i I.04 
66.77i .72 
97.78 
6 
Selection No. 201 F 3 .. 
10.2 
59.01 i 1.16 
56.35i1.04 
56.94i .75 
i° 3-44 
7 
Selection No. 201 F 4 . . 
n-S 
66.54i1.62 
68.73 i 1.27 
67-69i .80 
98. IO 
8 
Selection No. 201F 5 . . 
11 . 4 1 
65.96 i 1.21 
! 64.51 i 1.04 
64.8oi .72 
'101.75 
9 
Selection No. 201 F 6 . . 
n-S 
66.54 i 1.68 
66.88 i 1.10 
66.59+ -74 
; 100.02 
10 
Selection No. 201 
check. 
1 
10.3 
59 - 59 ±i -68 
58.49 i 1.21 
1 
58.65i .77 
101.41 
11 
Selection No. 201 F t 
(1914 seed). 
10.4 
60.17i3.53 
64.11i2.72 j 
62.43 i I . 92 
94-73 
1 
Average of the 
probable errors c .... 
i -757 
1.287 j 
O 
1 *>* 
00 
i 
I 
^100.07 
a Only 10 replications of strain No. n. 
b Selection No. 201 is the cross, Whatley X St. Charles White, made in 1914 and the filial generations 
descended from it. _ 
C P. E.=0.6; 4 S-J , S<P < . 
V n {n— 1 ) 
Average of all 3-row plats. 
adjusting the YIELDS 
The mean yield of each strain was computed first. These means are 
given under the heading, “Actual yields” in columns 3 and 4 of Table II. 
As has been noted, the field in which the comparison was made did not 
even look uniform, and, although the different lots were well distributed 
over the area, it was uncertain whether they had equal opportunity. 
It was assumed that the ratio of the yield of two alternate rows to the 
mean yield of the strains grown in them would be a good index of the 
productivity of the soil between them. Accordingly, the yield of each 
row was adjusted to this ratio. Thus, the yield of 15.4 pounds for row 
