Southern field crops (exclusive of forage plants) . Fig. 177. — The Chain Cultivatok fou Tillage avd for THE FALLEN SqU.\BES TO THE the southern part of Mississippi was more than tA\ice thisdistance, liringing the weevil at the end of 1909 to withinal)out ten miles of the Alabama line in the vicinity of iXIo-l^ile. In the fall of 1910 this insect invaded several coun-ties in the southeastern part of Alaliama. Probaldy itsextension northward will l)e somewhat less rapid than itseastward spread. Crossing the Rio (irande from ^Mexico about 1S92 ithas persistently
Southern field crops (exclusive of forage plants) . Fig. 177. — The Chain Cultivatok fou Tillage avd for THE FALLEN SqU.\BES TO THE the southern part of Mississippi was more than tA\ice thisdistance, liringing the weevil at the end of 1909 to withinal)out ten miles of the Alabama line in the vicinity of iXIo-l^ile. In the fall of 1910 this insect invaded several coun-ties in the southeastern part of Alaliama. Probaldy itsextension northward will l)e somewhat less rapid than itseastward spread. Crossing the Rio (irande from ^Mexico about 1S92 ithas persistently spread eastward and northward. Theniai) (Fig, 178) shows that by the close of 1909 the boll-wee^il occujiied the greater part of the cotton-growing COTTOy jysECTS 40&. 404 SOUTHERN FIELD CROPS areas of Texas and Louisiana, the soutiiern portion ofMississippi, and the southern parts of Oklahoma andArkansas. It may be expected to spread over the entirecotton-growing area of the United States within the next15 to 20 years. 371. Insect enemies of the boll-weevil. — The weevilhas fewer insect enemies than most crop pests. This isprobably because the mature weevil is protected ?\\ith ahard coat, and Ijecause in its stages of larva and pupa,when not thus protected, it is inclosed -n-ithin the squareor boll. However, there are some minute insects thatlay their eggs in the body of the immature boll-weevilwhile the latter is still in the scjuare. On hatching, thesesmaller insects cause the death of the pest. These minuteparasites have not destroyed a large proportion of the boll-weevils in Texas, and it remains to be seen whether thisclass of insects will be more useful in the moister climateof the Mississippi Valley and eastward. In order to utilize thes
Size: 1192px × 2097px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauth, bookcentury1900, bookdecade1910, booksubjectagriculture
