BOLL-WEEVIL COTTON IN TEXAS. 



to the ground are not reached by the direct light and heat of the 

 sun, nor is the ground heated sufficiently to dry the buds and kill the 

 weevil larvae inside. 



Prompt shedding of the weevil-infested buds, followed by 

 thorough drying and baking of the buds on the hut ground, explains 

 the beneficial effect of the dry, hot weather of Texas in checking the 

 reproduction of the weevils, so that it often is possible to set a crop 

 of bolls during a period of dry weather in spite of many weevils 

 Surviving the winter and attacking the cotton early in the season. 

 But with too much rain and warm weather in the spring, as in the 

 season of 1921 at San Antonio, there is danger of the plants growing 

 rank and becoming crowded in the field. The ground also is con- 

 tinuously shaded, and weevil larvae in fallen buds are sheltered and 

 protected from the sun to such extent that a later period of dry 

 weather does not have its normal effect of stopping the propagation 

 of the weevils and permitting a crop to be set. The advantage that 

 dry weather brings to fields of smaller and more open plants may be 

 lost entirely when the plants have grown too large before the dry 

 weather comes, as happened at San Antonio in the season of 1921. 



Thus the condition of overgrown, crowded fields needs to be rec- 

 ognized, even more clearly than in the past, as very unfavorable 

 from the standpoint of production: indeed, as most unfavorable. 

 Not only is there nothing more to expect in the way of setting more 

 bolls in the same season, but even the next year's crop is jeopardized 

 by allowing the fields of boll-weevil cotton to remain through the 

 season as a breeding place for weevils. 



Usually the fields are left until fall or until the plants are killed 

 by frost,when the weevils are ready to go into winter quarters, so 

 that a full quota of the insects is likely to be carried over to the next 

 season. Earlier destruction of boll- weevil cotton is the obvious need, 

 if improved cultural methods are not used, to avoid this hope!e?s con- 

 dition. The longer the boll-weevil cotton stands in the fields the 

 greater the danger of the injury being carried over to the next season. 



WEEVIL DAMAGE ON EXPOSED PLANTS. 



How closely the weevils are dependent in dr}^ weather upon the 

 shelter of the fields of overgrown boll-weevil cotton may be illus- 

 trated by facts observed at the United States Experiment Farm at 

 San Antonio, Tex., in the season of 1921 and brought to the writer's 

 attention by D. M. Simpson. The spring and early summer con- 

 ditions favored a rather large growth of the plants, so that the con- 

 dition of genuine boll-weevil cotton was generally attained. (PI. I.) 

 With the plants overgrown and crowded, meeting between the rows 

 and completely shading the ground, the weevils bred abundantly, 

 and a dense weevil population was maintained in spite of a rather 

 long period of dry weather in the latter part of the season. 



After the setting of a few bolls per plant in a short interval of 

 dry weather in the early flowering period, before the plants were 

 large enough to shade the ground completely, very few bolls escaped 

 the weevils in any of the fields that attained the regular conditions 

 of boll-weevil cotton. In later plantings the destruction was nearly 

 complete, but it was noticed by Mr. Simpson that bolls continued to 

 be set on isolated plants during the late-season period of dry weather. 



