May si, 1924 Comparison of Pima Cotton with Upland Varieties 
949 
Table IX.— Yield of seed cotton of the varieties compared in 1920,1921,1922, and 
1928 at the United States Field Station, Sacaton, Ariz., given in pounds and hy 
rows, and the total per plot 
Row numbers 
1920 
1921 
C2-13 
Pima 
C2-14 
Durango 
C2-15 
Lone Star 
C2-12 
Pima 
C2-14 
Durango 
C2-15 
Lone Star 
C2-13 
Acala 
1 . 
64.8 
52.5 
59.5 
80.6 
39.5 
61.8 
61.1 
2 _-. 
63.1 
51.1 
66.4 
78.5 
28.6 
57.4 
64.3 
3. 
74.4 
49.7 
64.2 
78.7 
20.2 
66.9 
67.8 
4... 
59.3 
47.9 
63.7 
66.1 
24.6 
61.7 
64.1 
5. 
63.6 
46.0 
64.4 
67.2 
22.7 
67.7 
65.0 
6 ... 
72.5 
49.4 
64.4 
65.1 
22.6 
65.8 
76.7 
7..... 
58.8 
63.7 
58.3 
62.9 
34.1 
78.1 
79.4 
Total... 
456.6 
360.3 
440.8 
499.1 
192.3 
459.4 
478.4 
Row numbers 
1922 
1923 
C2-14 
Pima 
C2-13 
Dur¬ 
ango 
C2-15 
Lone 
Star 
C2-12 
Acala 
C2-11 
Pima 
C2-10 
Dur¬ 
ango 
C2-14 
Lone 
Star 
C2-12 
Acala 
C2-9 
Harts¬ 
ville 
C2-13 
Me- 
bane 
1 . 
88.5 
59.3 
48.4 
62.8 
80.5 
70.6 
71.4 
91.2 
77.3 
78.1 
2 .. 
69.8 
54.4 
58.2 
58.4 
85.0 
82.1 
84.4 
83.8 
81.8 
74.4 
3.... 
70.8 
57.6 
48.2 
58.0 
86.1 
82.6 
81.0 
80.0 
77.3 
83.6 
4... 
64.2 
45.9 
47.7 
59.6 
82.7 
85.6 
93.7 
90.5 
78.7 
95.5 
5.. 
70.4 
57.7 
48.9 
60.8 
81.8 
72.3 
106.3 
80.4 
76.6 
88.3 
6 ... 
65.8 
53.0 
46.4 
60.6 
95.0 
92.0 
87.9 
90.8 
90.7 
84.8 
7.. 
82.9 
58.0 
55.7 
51.6 
80.8 
92.6 
64.5 
84.8 
94.3 
92.9 
Total. 
512.4 
385.9 
353.5 
411.8 
591.9 
577.8 
589.2 
601.5 
576.7 
597.6 
It will be observed in Table IX that Pima led all other varieties in yield dur¬ 
ing the first three years of the test. In 1923, a season which was very favorable 
for the production of all kinds of cotton, the Pima variety was third in rank 
from the standpoint of total production, though the differences were not signifi¬ 
cant in view of the wide variations between the individual rows. 
The comparatively high yielding capacity of the Pima variety in some of the 
valleys of the Southwestern States is explained by the ability of this type of cotton 
plant to retain under normal conditions from 70 to 90 per cent of the total bolls 
produced. By referring to the data on shedding in Tables V and VI, and to 
figure 4, it will be seen that the Pima plants were able to retain and mature over 
40 per cent more of the bolls than the best adapted Upland varieties grown under 
similar conditions in 1922 and 1923. 
While the total yields of seed cotton have been larger for the Acala than for 
other Upland varieties during the three years in which this variety has been in¬ 
cluded in the comparison, the differences in row yields are so large that the totals 
may not be significant. 
Greater irregularities appear in the yields of Durango and Lone Star than in 
those of Pima and Acala, and also wider variations in the rates of shedding. 
Such fluctuations may indicate a lack of stability in these varieties, as though 
less adapted than Pima and Acala to withstand the extremes of the summer 
climate. 
In 1922 the behavior of the Acala and Hartsville varieties in late plantings was 
compared at Sacaton. For another purpose a very late planting of Acala was 
made, on June 22, at the side of a Hartsville planting on June 5. Even with this 
handicap of more than two weeks the Acala rows were nearly as productive as 
the Hartsville, as shown in Table X. In 1923 the two varieties were compared 
at different dates of planting, April 30 and May 20. The soil where these plant- 
