﻿16 



BULLETIN 1374, U. S. DEPARTMENT OF AGEICULTURE 



The data in this table are shown graphically in Figure 7. In the 

 graph the figures of Table 14 are reduced to number of forms per 

 plant. A fourth line in the graph shows the development of the 

 infestation in mature green bolls on the plants during the same 

 period of time. A great decrease occurred in the number of forms 

 on the plants between the middle and the end of July. Reference 

 to Table 14 shows that this was due to both shedding and absence 

 of new fruiting. Following the irrigation, however, there was a 



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Fig. 6. — Daily average number of total blooms and blooms infested with the pink boUworm 

 per acre, 1921 and 1922 records 



great increase in fruiting, and shedding practically ceased for a 

 time. 



The early infestation (fig. 7) was so light that, even if it caused 

 shedding, this could have had no appreciable effect on the total 

 shed, which was very great at that time. During the period of the 

 second growth a much greater part of the shed forms was infested. 

 Comparing this, however, with the infestation of blooms on the 

 plants (fig. 6), it will be noted that an equally high percentage 

 of the blooms on the plants was infested. This indicates that even 



