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The Cotton Bollworm. Unlike the cotton worm, this insect is 

 by no means confined to America, nor is it confined to cotton as a 

 food plant. It is known in many other parts of the world, and 

 it can not be surmised at the present time whether it has been 

 carried from some one point or whether it is indigenous over its ex- 

 tremely wide range. Its food plants vary in an extraordinary degree. 

 In this country it is one of the principal enemies of cotton, of com, 

 and of the tomato. 



The cotton bollworm, the corn earworm, and the tomato fruit 

 worm are all the same species. In addition to these crops, it feeds 

 upon peas and beans, tobacco, pumpkin, squash, okra, and a num- 

 ber of garden flowering plants, such as cultivated geraniums, gladi- 

 olus, mignonette, as well as a number of wild plants. 



"Undoubtedly for several years the boll weevil has caused a 

 loss of about 400,000 bales of cotton annually. Although farmers 

 in older regions, in many cases, are increasing their production, 

 there is loss in the newly infested regions which offsets that gain. 

 A conservative estimate shows that since the weevil has invaded 

 this country it has caused a loss of 2,550,000 bales of cotton, at a 

 value of about $125,000,000." (Farmers' Bui. 344 U. S. D. A.) 



"When first hatched, the bollworm looks much like the cotton 

 worm. It is rather darker in color, but also walks like a looper, 

 or measuring worm. It feeds at first near the eggshell, and then 

 begins to wander away, crawling from one leaf to another, until a 

 young bud or boll is found, into which it bores. Frequently sev- 

 eral days pass in this search for a boll, and rarely the worm may 

 reach full growth upon a diet of leaves. It is during this early, 

 wandering leaf-feeding existence that the insect may be destroyed 

 by arsenical poisons, as is true of the cotton worm. When the 

 young worm enters the flower bud the involucre flares open and 

 the young bud or young boll finally drops. This "shedding" of 

 cotton is, however, not caused by the bollworm alone. Other insects 

 are concerned in the damage, and the flaring and dropping occa- 

 sionally occurs when no insect injury can be found. A very consid- 

 erable amount of damage may be done in this way, as a single young 

 larva will travel from bud to bud, deserting each before it falls. The 

 bud pierced just before opening is forced into premature bloom, 

 but the worm usually feeds upon the stamens and pistil, render- 

 ing it incapable of fructifying. As the bollworms grow, they begin 

 to vary greatly in general appearance. Full grown worms may be 

 found of almost every intermediate stage of color between light 

 green and dark brown or rose. They may be unstriped and un- 

 spotted, or they may possess dark stripes or black spots. These 

 color varieties are not caused by different food, since many varia- 

 tions occur in specimens feeding upon the same plant. Upon cotton 

 the larger worms take the larger bolls, the young ones having con- 

 fined themselves in the main to the flower buds and the newly 

 formed bolls. They then practically progress downward, the young 

 ones being found mainly upon the top crop, while the older ones 

 bore into the older bolls of the middle crop, the bottom crop being 



