July 28,1923 
Growth of Fruiting Parts in Cotton Plants 
203 
GROWTH OF LONE STAR BOLLS IN TEXAS 
Two series of measurements of the growth of bolls were obtained on 
the Lone Star variety near Greenville, Tex., 1922, one series representing 
the growth of bolls at the beginning of the flowering season, the other of 
bolls produced from later flowers, the last that were able to set bolls 
under the local conditions of drought. Measurements of boll length 
were recorded the second day after the bloom, and continued daily until 
it was certain that the maximum length had been attained. The young 
bolls at 2 days of age were about 16 mm. long, increasing in length 
approximately 2 mm. per day thereafter until they were about 12 days 
old, or about 37 mm. long. After reaching this age the growth rate was 
much slower, the average maximum boll length of about 41 mm. having 
been recorded 8 days later, or 20 days after the date of flowering. Table 
IX presents the mean daily length of these bolls. 
It is interesting to note that no increase in length was found after the 
twentieth day from the bloom. Many bolls reached their full length in 
16 days, the mean period from bloom to maximum length being 17.3 
days in the first series of bolls and 17.1 days in the second. Of course, 
these records should not be taken to indicate that development of the 
boll is complete when the full length is reached, since 17 days represent 
less than half of the period from the bloom to the open boll. 
Table IX. —Daily increase in length of Lone Star bolls , Greenville, Tex., 1922 
Number of 
days after 
flowering. 
Length of bolls 
from blooms 
open July 21 to 
July 26. 
Length of bolls 
from blooms 
open Aug. 3 to 
Aug. 8. 
Mm. 
Mm. 
O 
17. 6 
i 4 - 77 
3 
i 9 - 77 
16. 77 
4 
| 2 i -35 
j 18. 18 
5 
i 23.35 
19.4 
6 
2 5 . 67 
20. 77 
/ 
28. 62 
22.2 ! 
8 
30. 02 
24- 73 
9 
32.27 
26. 45 
10 
33- 82 
28. 55 
11 
36. 1 
30-95 
12 
37 - 9 
34- 16 
13 . 
39 - °5 
35- 68 
14 
40 . 35 | 
36. 68 
15 
4 1 - 15 ! 
37 - 5 
16 
4i- 85 | 
38. 27 
D 
42. 25 j 
38- 86 
18 
42. 67 | 
39 - 13 
19 
43 - 15 
39 - 27 
20 
43-17 ! 
j 
39 - 36 
j 
MATURATION PERIOD OF LONE STAR BOLLS 
It will be noted in Table IX that the later bolls are consistently smaller 
than the early ones. This shows the inhibiting effect of the drought 
which checked the growth of plants after the first week in August. The 
smaller size of the bolls, however, did not result in a shorter period of 
maturation. Data on the number of days from bloom to open boll, 
