11 



which its spread will be prevented or at least checked by climatic con- 

 ditions. During- the past 3"ear it has been found that there is at least 

 one full o-eneration less at Terrell, Tex., than at Victoria, Tex., 275 

 miles south of that place. With the very I'apid multiplication of the 

 ])est, this means g-reatly lesseiied actual damage. The ,time when the 

 maximum number of weevils per acre is produced is made considerably 

 later, with a consequent manifest advantage to the crop. The lessened 

 number of generations is due to three principal factors: (1) Later 

 emergence from hibernating quarters; {'2) greater time required for 

 the development of the several stages; and (3) the earlier date of the 

 first killing frost. These considerations would, theoretically at least, 

 cause the weevil problem to become a much less serious one in extreme 

 northern Texas than it has been in regions that have heretofore been 

 infested, and the observations of the last season bear out this supposi- 

 tion. However, it is to be expected that there will be some adaptation 

 on the part of the weevil to the climatic conditions in newly invaded 

 regions, and this introduces considerable uncertainty in any prediction 

 regarding future damage. The present indications are that the great- 

 est damage b}" the pest will always be in the region south of the lati- 

 tude of Dallas, Tex. 



To the east there has been a general extension of the infested terri- 

 tory of about 5t) miles. The pest has been found east of the Red River 

 at three points in Louisiana, namel}', Lockwood, Grand Ecore, and 

 Shreveport. In that State the g-reater portion of six parishes is known 

 to be generally infested, while in three others the weevils are known 

 to occur in certain localities. Special opportunities for studying this 

 spread were given by the cooperation which the Bureau of Entomology 

 carried on with the Louisiana crop pest commission. It was found that 

 there was an advance earl}' in the fall due to the fact that the weevils 

 were carried from place to place in seed for planting purposes. This 

 was followed by considerable increase in territorj^ due to the convey- 

 ing of the seed cotton to the gins, and, most important, there was an 

 advance due to an actual migration in August and September, which 

 in man}' cases reached far be3^ond the limits of the territory covered 

 b}" the first two means which have been mentioned. 



At frequent intervals during the past season (190i) accounts of the 

 occurrence of the boll weevil at various points far beyond the limits 

 of the infested territory indicated upon the accompanying map (fig. 5) 

 have appeared in the newspapers. It seems likely that the pest may 

 at an}^ time be carried to points far outside of the present infested 

 teiTitory 1;hrough the ordinary shipments of cotton products. There 

 is also some possibility that persons who have received live speci- 

 mens from Texas for experimentation with supposed remedies may 

 inadvertently introduce them into uninfested fields. In consequence 

 of these probabilities, the Bureau of Entomology has devoted special 



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