Losses to cotton, what to look for and where to find it, being one of a series of articles in relation to crops, their common diseases and insect pests to which they are subject . ll and inclosure. formation to the adult stage. The recently emerged in-dividuals are light yellowish in color, but pass to a gray ornearlv black shade in a few weeks time. In the field tlie most conspienons indication of thepresence of the boll weevil is the flaring and falling of greatnumbers of squares. However, unfavorable climatic con-ditions and careless cultivation fre(]uently cause muchshedding. If excessive
Losses to cotton, what to look for and where to find it, being one of a series of articles in relation to crops, their common diseases and insect pests to which they are subject . ll and inclosure. formation to the adult stage. The recently emerged in-dividuals are light yellowish in color, but pass to a gray ornearlv black shade in a few weeks time. In the field tlie most conspienons indication of thepresence of the boll weevil is the flaring and falling of greatnumbers of squares. However, unfavorable climatic con-ditions and careless cultivation fre(]uently cause muchshedding. If excessive shedding be noticed and the squaresupon being cut open show a white, curved grub that has fedupon the contents, there is little doubt that the l)oll weevilis the insect causing the damage. The boll weevil passes the winter in the adult the spring and throughout the fruiting season of cottonthe eggs are deposited by the female weevils in the cavitiesformed by eating into the fruit of the plant. The squares are greatly i)referred as food and as placesfor depositing eggs. As long as a large supply of s(juaresis present the bolls are not damaged to any serious COTTON BOLL WEEVIL Mature boll cut open at left, showing full-grown larva; the one at the right notcut, and showing feeding punctures and oviposition marks. The bolls, therefore, have a fair chance to develop as longas squares are being formed. Whenever frost or other un-favorable weather causes the plants to cease putting onsquares, the weevils attack the bolls. The cotton boll weevil, so far as known at present,has no food plant other than cotton. In the fall when frosts occur, immature stages of de-velopment of the boll weevil may be found in the scjuares orbolls. Provided food supply is sufficient, many of theseimmature stages continue their development at a very slowrate and adults finally emerge. Thus there may be a some-what continuous ])roduction of adults during the winter. 10 Ordinarily, however, t
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