﻿STUDIES OF THE PINK BOLLWOEM IN MEXICO 



29 



eradication in several large areas. In these areas, however, no effort 

 was made to eliminate possible alternate food plants. 



Very extensive searches have been made in the United States to 

 find infestation by the pink boUworm in okra and other malvaceous 

 plants growing in noncotton zones and in their immediate vicinity. 

 In no case has any infestation ever been found in any of these plants. 



The records from Mexico and those from Egypt and other countries 

 have shown clearly that the insect can develop in plants other than 

 cotton. Taking all the available information together, the conclusion 

 seems to be warranted that, in the presence of enormous numbers of 

 the insect, such as are found in Mexico and Egypt, there are occasional 

 more or less aberrant individuals which attack plants other than 

 cotton. With such an attenuated infestation as has occurred in the 

 United States, the volume of the moths is so small that the chance 

 of attack on other plants is negligible. 



Fig. 10. — Group of cotton plants in tests to determine distance of flight, fenced for protection against 



animals 



DISSEMINATION BY FLIGHT 



In 1921 and 1922 F. F. Bibby conducted experiments to determine 

 if possible the distance the pink bollworm moth would normally 

 cover by flight. vSmall groups of plantings (fig, 10) were made at 

 isolated points distant from cotton fields and kept under observa- 

 tion to aetcrmine whether they became infested. Seed free from 

 pink bollworms was used. 



In 1921, there were 8 small groups of plants at intervals of 1 mile 

 to the north of the fields on the Thihualilo plantation, which was the 

 nearest cotton to these plantings. Each group consisted of about 

 a dozen plants, which did not attain any great size and bore little 

 fruit, making examination easy. Thorough examinations precluded 

 the po.ssibility of motlis developing in one group of plants and in- 

 festing the next one. 'J'he results of the tost are given in Table 23. 



