1929 - Baerg, W. J., D. Isely, and H. H. Schwardt. Report on entomological work 1928- 

 29. Ark. Agr. Expt. Sta. B. 246:50-53. 



Serious annual injury to cotton by the boll weevil occurs over a comparatively 

 small area during the growing season. The damage caused after the weevils dis- 

 perse late in the summer is usually relatively light under average conditions. 

 Some localities are subject to sporadic outbreaks in certain years. 



The weevil regularly occurs in fertile land, bordered by well-drained hill 

 land favorable for hibernation. In such land, the plants usually form squares late 

 in the season, in which the weevils are able to reproduce in large numbers before 

 going into hibernation, and direct control is advisable. 



Although sandy hills are ideal hibernating quarters, the number of weevils 

 that develop to go into hibernation is often comparatively small, since a drought 

 late in the summer and autumn often checks the setting of the squares on cotton 

 grown on light soil. Even when large numbers hibernate and a heavy infestation 

 occurs early in summer, a period of hot dry weather may stop an infestation that 

 appears to be well under way. 



On flat lands that are not well drained in winter, the weevils do not hibernate 

 successfully except on knolls, etc. If the areas that require winter cleaning are 

 not large, control of the weevil by destroying it in hibernation is recommended. 



1929 - Fenton, F. A., and E. W. Dunnam. Biology of the cotton boll weevil at Florence, 

 S. C. U. S. D. A. Tech. B. 112, 75 p. 



The average winter survival during 4 years' observation was 3.27%. The best 

 protection was given by piled cotton stalks. Other shelters, in the order of their 

 importance, are corn stalks, pine straw, Spanish moss, sawdust or shavings, and 

 oat straw. There was a definite relation between rate of emergence from hiber- 

 nation and type of shelter; weevils in pine straw, corn stalks and Spanish moss 

 continue to emerge later than those in other shelters. 



Migration to cotton after emergence occurred from mid-May to late in June 

 in 1925. Weevils emerging before cotton came up in 1925 and 1926 sometimes re- 

 mained active in cages for several days or again entered hibernation. A few 

 weevils began to hibernate early in September and most of them did so late in 

 September and October. 



1929 - Isely, Dwight. Ark. Agr. Expt. Sta. 41st Ann. Rpt. B. 246: 51-52. Dec. 



Most regular occurrence of boll weevil in destructive numbers is in fields 

 on fertile land, bordered by well-drained hill land favorable for hibernation of the 

 weevil. On flat lands, not well drained in winter, the boll weevil does not hiber- 

 nate successfully. 



1931 - Calhoun, P. W. A correlation of the date of emergence and percentage of survival 

 of the cotton boll weevil with the date of their installation in hibernation cages. 

 Fla. Ent. 15(3):41-48. 



To determine the effect that the date of confining Anthonomus grandis Boh. 

 in hibernation cages in the autumn might have on the date of their emergence or 

 the percentage of their survival, the data from 1 1 groups of hibernation cage 

 experiments in Florida and 1 in Mansura, La. were examined. In 9 groups of 

 cages, placed either on the ground in open fields, or on the ground or in trees in 

 woods, the date of confining the weevils in the autumn apparently did not deter- 

 mine to any considerable extent the date of their emergence in the following 

 spring, but, in 5 groups on the ground in open fields, the date had a marked effect 

 on the percentage of emergence. The highest percentages of survival always came 

 from cages in which the weevils were introduced moderately late in the autumn. 

 In 4 groups of cages placed in trees in woods, the date of confinement in the 

 autumn seemed only slightly to affect the percentage of survival. 



This, however, should not be interpreted to mean that the destruction of the 

 green cotton stalks early in the autumn would prove of little benefit in localities 

 where weevils are supposed to hibernate largely in mossy trees. Early stalk 

 destruction greatly reduces the number that hibernate. Moreover, as cage hiber- 

 nation tests have been found unreliable as a means of predicting the time of ap- 

 pearance of boll weevils in the cotton fields, it would be unsafe to conclude that 



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