L5o 



SB 

 818 

 C578 

 ENT 



Circular No- 167. issuedJanviaiy is. 1913. 



United States Department of Agriculture, 



BUREAU OF ENTOMOLOGY. 



L. O. HOWARD, Entomologist and Chief of Bureau. 



THE MOVEMENT OF THE COTTON BOLL WEEVIL IN 1912. 



By W. D. Hunter and W. D. Pierce, 

 Of Southern Field Crop Insect Investigations. 



The movement of the boll weevil durmg the season of 1912 is of 

 special interest on account of the checks the insect received by the 

 very unusual clmiatic conditions of the winter of 1911-12. Not- 

 withstanding this setback the insect has made a net gain of 7,300 

 square miles. 



The map (fig. 1) shows the extent of the infested territory in 1912 

 and in various preceding seasons. There are three points that are 

 especially noteworthy in connection wath this map. One of these is 

 the failure of the insect to extend into central Oklahoma as far as it 

 did in 1906, The second is a comparatively small loss of territory 

 along the northern border in Arkansas and ^lississippi. The third 

 is the fact that the weevil has been able to maintain itself prac- 

 tically to the western limit of the area of continuous cotton culture 

 in the central part of Texas. The western limit of cotton culture in 

 Texas is far beyond the Hne showing the limit of the weevil-infested 

 territory, but the intermediate area has very few cultivated fields, 

 separated by long stretches of pasture lands. 



The line marking the Imiit of the infested territory at the end of 

 the season of 1912 runs as follows: 



In Texas, beginning at Del Rio on the Rio Grande in Valverde County; thence 

 including Roosevelt in western Kimble County, Menard ville in Menard County, 

 Abilene in Taylor County, Jacksl)oro in Jack County; retreating between Jacksboro 

 and Decatur, excluding Arlington in Tarrant County, Letots, Mesquite, Lancaster, 

 Richardson, Farmers Branch, and practically all of Dallas County, but including 

 Farmersville in Collin County; excluding Sherman in Grayson County; leaving the 

 State at the northeast comer of Fannin County. 



In Oklahoma, from a point opposite the northeast comer of Fannin County, Tex., 

 the line follows the river valley, includes Hugo, and leaves the iState in the northeast 

 comer of McCurtain County. 



In Arkansas the Une includes Mena in Polk County, the lower edj 

 County, Conway in Faulkner County, Ckrendon in Monroe Count 

 the State just below Helena. /cJ^"^ 



71306°— 13 / ' 



ffS^ 4 1913 



