18 



number of wild cotton trees growing in the vicinity of dwellings or 

 growing entirely wild are always infested, and here the weevils are 

 more numerous, but never as numerous as on the cultivated Egyptian 

 cotton. At one locality, where a large number of kidney cotton trees 

 were growing (about 50 plants, some of them probably 20 years old), 

 it was found that at least one out of every twenty squares had been 

 punctured by the first week in March. From Mr. Schwarz's report 

 it does not seem that there is a very promising outlook for cotton 

 raising in Cuba. The presence of wild perennial cotton, upon which 

 the weevil probably exists everywhere, will alwaj T s be a source of 

 danger. The long moist seasons and mild winters will form more 

 favorable conditions for the pest than will occur anywhere in the 

 United States. 



PROSPECTS. 



The investigations of the life history of the weevil that are referred 

 to in detail in the following pages have indicated that the most im- 

 portant elements in limiting the spread of an insect — namely, win- 

 ter temperatures and parasites — in this case offer no assurance that 

 the pest will soon be checked. For the past ten years, except where 

 local unfavorable conditions have interfered, it has advanced annu- 

 ally a distance of about 50 miles. The insect is undoubtedly chang- 

 ing its habits and adapting itself to climatic conditions in new regions 

 that it is invading. It is undoubtedly true that it has acquired an 

 ability to withstand more severe frosts than occurred in the vicinity 

 of San Antonio in 1895. Except in a few particular regions, however, 

 it does not seem that the continued spread will be as rapid as it has 

 been. The countiw between Gonzales County and the Red River is 

 practically a continuous cotton field, and the prevailing winds have 

 undoubtedly favored the northward spread of the insect. Similar 

 conditions will now favor a rapid extension into the Red River valley 

 in Louisiana, and likewise there seems no doubt that the spread will 

 be rapid in the Yazoo valley in Mississippi; but in most other situa- 

 tions throughout the belt the cotton fields are smaller and more iso- 

 lated than is the case in Texas; consequently it is to be supposed 

 that the spread of the pest will be retarded somewhat. 



Basing estimates on a careful study of the distance the boll weevil 

 has traveled each year, as well as upon some attention that has been 

 paid to the means whereby it reaches new territory, referred to more 

 in detail hereafter (p. 94), it seems safe to predict that in from fifteen 

 to eighteen years the pest will be found throughout the cotton belt. 

 During the time it has been in Texas there has been no tendency 

 toward dying out, and in south Texas the pest is practically as trou- 

 blesome, except in so far as it is affected by changes in managing the 

 crop, as it was in 1895. In Mexico, where it has existed for a much 

 longer period, it is apparently as plentiful as ever. Careful attention 

 that has been paid to the study of parasites and diseases, as well as 



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