29 



only had a great many of the weevils been killed, but the numbers 

 had been diminished b}^ reason of the very limited extent to which it 

 was possible to raise cotton. Both 1900 and 1903, however, were 

 exceedingly favorable for cotton. Early planting was possible, and 

 there was an abundance of rain throughout the season. The crop 

 was so far advanced by the time the weevils became numerous that a 

 very fair yield was made, although in neither of the cases was any 

 top crop whatever produced. Whenever a series of years of scanty 

 rainfall is followed b}^ one of normal precipitation the weevil will 

 temporarily be comparatively unimportant. The most disastrous 

 seasons will be those in which the rainfall is excessive and planting 

 unavoidably thrown late. 



One of the most interesting features of the situation which devel- 

 oped during the season of 1901, which will be dealt with more fully 

 in the succeeding pages, was the fact that the infested region extended 

 eastward much more rapidly than northward. Careful examination of 

 the portions of Indian Territory and Arkansas which the weevil is apt 

 to reach first has failed to reveal any infestation; in fact, on the north 

 the limitation of the infested territory remains practically^ the same 

 as at the end of the season of 1903. This applies, however, only to 

 the total infested area in which even isolated colonies have been found 

 to exist. There has been, nevertheless, a gradual northward advance 

 of the region of gross infestation. Its advance has extended from 

 the latitude of the northern portion of Ellis County to about the 

 latitude of the southern portion of Collin County. This situation 

 raises the question of whether the pest has not reached a northern 

 limit beyond which its spread would be prevented or at least checked 

 by climatic conditions. It has been found that there is at least 

 one full generation less during the season at Terrell, Tex., tlian at 

 Victoria, Tex., 275 miles farther south. This naturally means a 

 greatly lessened degree of 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. It was pointed out in a 

 previous bulletin (i. e.. No. 15) that the considerations just men- 

 tioned would probably cause the weevil problem to be much less 

 serious in extreme northern Texas and similar localities than 

 has been the case in regions that have hitherto been infested. Never- 

 theless, it is to be expected that there will be some adaptation on the 

 part of the weevil to the climatic conditions in newl}^- invaded regions, 

 and this element introduces considerable risk in any prediction regard- 

 ing future damage. From the present outlook, however, it may be 



