COTTON IN WEEVIL-CONTROL EXPERIMENTS 9 
Although the field became reinfested with weevils after square 
removal and poisoning, the degree of infestation was much less than 
in untreated early-planted fields on other parts of the experiment 
farm. Possibly a more effective control might have been obtained 
if the measures had been applied earlier than June 12, as fewer 
infested squares would have been shed before the square-stripping 
operation. 
PLANT GROWTH DURING THE FRUITING PERIOD 
Records of the nodal growth of the cotton plants, the rate of 
flowering, and ‘the extent of boll shedding were obtained from each 
of the four plantings. Comparisons of the rate of formation of 
internodes were obtained from 10 representative plants in each plant- 
ing, while the flower counts and boll sheds were recorded from 50-foot 
sections of rows. 
The records of plant development following the appearance of 
squares were obtained from diagrams of the same plants which were 
used in comparing the rate of growth during the seedling stages. 
These diagrams were made at weekly intervals throughout the period 
of fruiting of the plants, the final records having been made on August 
11, after growth had practically ceased. 
A comparison of the rate of formation of internodes on plants in 
the successive plantings is shown in Table 6, which gives the average 
number of nodes on 10 plants of each planting on the date when 
squares were first recorded and 14, 28, and 56 days later. As the 
first squares were recorded on different dates, it should be noted that 
the nodal development of the plants in each planting is compared 
during similar stages of growth and not on the same dates. 
 TasBe 6.—Development of nodes on the main stalk during the fruiting stage of cotton 
plants grown in successive plantings at San Antonio on four different dates 
Number of nodes at stated intervals after first appearance of squares 
i 
Date of planting, pau | 14-day interval | 28-day interval | 56-day interval 
soe TECORU SG RA cea ee | ee ee | Potaly | Prob- 
ane ; : ; ins, able 
n- n- n- crease | error 
Actual anes Actual ae Actual a 
20) 1g (0 Ne ee eas June 1 6. 5 11.2 4.7 14.8 3.6 18.6 3.8 2 +0. 15 
{ORB I2As a aa ae June 8 7.0 TL 4.5 14.9 3.4 18. 2 3.3 1152 =) 22 
Boley yy phe 2 aac Gon 6. 2 10. 9 4,7 14. 2 3 16.9 P27) 10.7 | + .37 
ML AY LQ or June 15 5.9 11.8 5.9 3.3 : 3. 8 13.0] + .22 
The average number of nodes produced on the main stalk during 
the first period of 14 days after the appearance of squares was 4.7, 
4.5, and 4.7 nodes, respectively, on plants of the first three plantings. 
The planting of May 12, however, formed 5.9 nodes during this 
period. During the second period of 14 days the rate of formation 
of nodes was much slower, the increase in number of nodes having been 
3.6, 3.4, 3.3, and 3.3, respectively. The final period comprised 28 
days, but the increase in number of nodes was only 3.8, 3.3, 2.7, and 
3.8, or about the same as during the preceding period of 14 days. 
The total number of nodes formed during the entire period of 56 
davs after the appearance of the first squares was 12.1 nodes on plants 
20718°—25},——2 
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