Spread of the boll weevil between 1892 and 1921 is plotted on this map from the Farmer's 

 Bulletin, February 1922. 



Texas to North Carolina and as tar north as south- 

 eastern Missouri. The beetle eventually settled vir- 

 tually everywhere cultivated cotton grew. 



Three or four years after an invasion, crop losses 

 caused by the boll weevil often exceeded 80 percent, 

 bringing financial ruin to many farmers. The de- 

 struction led to the abandonment of numerous mar- 

 ginal cotton-producing areas. Many farmers switched 

 to crops other than cotton. Scholars often list the re- 

 sulting economic hardship as one cause of the mas- 

 sive migration of farmers and farm laborers — partic- 

 ularly African-Americans — from the rural South to 

 northern cities in the early twentieth century. In spite 

 of the upheaval, however, the forced diversification 

 away from a one-crop economy has been called a 

 blessing in disguise, because it ultimately led to 

 greater economic stability throughout the South. 



The efforts to fight back against what became a 

 hundred-year plague also led to innovations in 

 chemistry, agricultural practice, and mechanical de- 

 sign. Many southern universities established ento- 

 mology departments to study ways to combat the boll 

 weevil. But success was halting. In 1903 the Texas 

 Legislature offered a $50,000 cash reward — a huge 



An Invasion 

 Unfolds 



sum for its day — to anyone who could devise a way 

 to control the insect. No one collected. And many 

 of the early responses to the boll weevil, particularly 

 chemical treatments, created problems of their own. 



Compounds of arsenic were first used against the 

 boll weevil in 1919, with some success. Just two years 

 later, U.S. cotton farmers were applying calcium ar- 

 senate dust to their fields at a rate of ten million pounds 

 a year. It remained the principal control method un- 

 til after the Second World War, when DDT and its 

 derivatives came into widespread use. But calcium 

 arsenate is toxic to invertebrates, fish, birds, and mam- 

 mals, and it is a known human carcinogen. Its residue 

 is still present in many southern soils. 



DDT and the chemical insecticides that were sub- 

 sequently developed initially offered hope of curbing 

 the boll weevil for good. But the pest resisted control 

 and heavy chemical use added economic and envi- 

 ronmental costs to cotton production. The boU wee- 

 vil remained the most important cotton pest through- 

 out most of the South as the twentieth century closed. 



Yet today the boll weevil is on the run in the U.S. 

 A massive eradication program, funded by growers, 

 afflicted states, and the USDA, began in 1978. Traps 

 baited with synthetic boll-weevil pheromone indi- 



1862 Farmers in northern Mexico first report 

 boll weevil destroying cotton crops. 



1894 U.S. Departme 

 the first report 



1843 Swedish entomologist Carl H, Boheman scientifically describes 

 the boll weevil (/Anthonomus grandis) from Mexican specimens. 



1892 Boll weevil enters 

 the United States. 



32 



NA IURAI IIIS M)I<.Y February 2006 



