May 3i, 1924 Comparison of Pima Cotton with Upland Varieties 
939 
Table II .—Dates when variety plantings were irrigated and when over 1 inch of 
rainfall occurred at the United States Field Station t Sacaton , Ariz ., in 1922 
and 1928 a 
1922 
Month 
Date of 
rain 
Date of irrigation 
Variety 
— 
Acala 
Durango 
Pima 
Lone 
Star 
April...... 
28 
28 
July.... 
7 
7 
7 
7 
Do...... 
25 
25 
25 
August... 
1 
Do....... 
8 
8 
Do-...-.... 
15 
25 
Do......... 
September. ... 
31 
Do.. 
• 15 
Do_ 
19 
19 
1 
1923 
Date of irrigation 
Month 
Date 
of rain 
Variety 
Harts- 
viile 
Durango 
Pima 
Acala 
Mebane 
Lone 
Star 
May..... 
29 
29 
29 
29 
29 
29 
June... 
29 
29 
29 
29 
29 
29 
July.... 
13 
Do-.-.-... 
24 
24 
24 
24 
24 
24 
August..... 
6 
6 
Do.....— 
7 
7 
7 
7 
Do.-.. 
21 
21 
21 
21 
21 
21 
September... 
1 
1 
1 
l 
1 
1 
Do.. 
11 
1 
11 
11 
11 
11 
11 
a On Aug. 25, 1922, and on Oct. 2, 1923, the varieties were all watered to permit the proper maturing 
of the crop and had no effect on the shedding. 
In 1922 and 1923 after the plants were thinned, and before any flowers had 
opened, a section consisting of 25 representative plants was selected in one of 
the interior rows of each variety. Detailed notes were taken daily on the 
behavior of these plants throughout the remainder of the season. 
The height of the individual plants in each of the 25-plant sections was meas¬ 
ured at weekly intervals through the season until growth had practically ceased. 
The number of flowers produced each day was recorded from the time of the 
appearance of the first flower until September 15. A small white tag bearing 
the date of flowering was fastened to the pedicel of each flower in such a manner 
that it remained attached to the young boll, even after shedding. Collections 
were made daily of the tags which had fallen with shed bolls, and the dates 
recorded. Thus a record of flowering and shedding was obtained for each day 
throughout the season. In 1923 the date of opening was recorded for each boll, 
which determined the period required for each boll to reach maturity. 
