4 THE STATUS OF THE COTTON BOLL WEEVIL IN 1909. 



combined, however, served to give it such a check as it has never 

 experienced in this country. At many points in Texas and Louisi- 

 ana all records for summer temperature were exceeded. For several 

 days the thermometer registered over 110° F. and in some cases 114° 

 F. was reached. On the surface of the ground the temperature was 

 naturally even higher. 



No one who traveled in Texas during the season of 1909 could 

 have failed to notice the effect of the abnormal climatic conditions 

 on crops of all kinds. The cotton generally grew to from one-fourth 

 to one-half of the normal size. The conditions were so adverse that 

 even variety characteristics were more or less obliterated. The 

 same conditions acted on the boll weevil. In fact, through large 

 productive areas in central and northern Texas the insect was so 

 reduced in numbers that it did not injure the crop to any extent 

 whatever. 



It is interesting to note that the experience of the season of 1909 

 shows conclusively that while a certain degree of dry weather is 

 greatly to be desired for the controlling effect it has upon the boll 

 weevil, dryness beyond a certain degree not only affects the boll 

 weevil adversely, but also the cotton plant. In fact, it became evi- 

 dent that the cotton plant was so stunted by the dryness that it was 

 unable to derive any advantage whatever from the comparative 

 scarcity of the weevils. 



DISPERSION OP 1909. 



As regards dispersion, the season of 1909 was almost as unusual 

 as in other respects. In one region by far the largest advance ever 

 recorded was made by the weevil. This covered 120 miles of ter- 

 ritory in southern Mississippi. At the same time in Oklahoma the 

 greatest advance was only 30 miles, while throughout the greater 

 portion of that State the line was extended only about 10 miles. 

 A notable feature of the year's dispersion was the failure of the 

 insect to extend its range considerably into the Yazoo Delta in Mis- 

 sissippi. During the preceding year an exceedingly light infestation 

 reached the extreme southern portion of the delta. This was the 

 vanguard of a fhght that was rather extended. During the season 

 of 1909 the insect extended its range in that quarter only about 15 

 miles. Why there should be an advance of 120 miles in southern 

 Mississippi and only 15 in the northern portion of the State at first 

 seems obscure, but studies that have been made indicate the expla- 

 nation very clearly. One of the primary reasons for the dispersion 

 movement of the weevil seems to be its inclination to obtain fresh 

 food, and cotton squares in which to breed. Where the cotton fields 

 are small and separated by considerable distances, this instinct 

 causes the weevils to fly over a large extent of territory. On the 

 other hand, where cotton fields are numerous it is unnecessary for a 

 considerable advance to be made. In other words, a region of light 



