INSECTS AFFECTING CORN 113 



over winter. "When it is feared that they are to attack 

 a cornfield, a strip a rod or so wide, plowed and pulverized 

 to fine dust, is effective in checking their progress. Fur- 

 rows are often plowed about a field and a log dragged along 

 the furrow to make a fine dust in it. The little insects, 

 owing to the moving of the dust, have difficulty in crossing 

 the furrow. Holes bored with a post auger at intervals 

 along the furrow serve as efficient traps to catch large num- 

 bers of the insects. They may be killed in these holes by 

 burying them or by pouring a small quantity of kerosene on 

 them. Strips of tar are also effective in checking their 

 progress. 



149. Grasshoppers, sometimes do serious injury to corn. 

 Like chinch bugs, they attack the corn, as a rule, only after 

 the other crops have been destroyed or harvested. The 

 edges of the fields next to grass land or grain fields are usu- 

 ally attacked first. Fall plowing is one of the most effective 

 methods of preventing the ravages of grasshoppers. They 

 may be killed in large numbers by spraying a strip along 

 the cornfield with arsenate of lead, mixed in the proportion 

 of 5 pounds to 100 gallons of water. The cornstalks thus 

 sprayed cannot be used safely as feed for stock. 



150. Grain Weevil. Corn in storage is sometimes 

 attacked by the grain weevil. These insects eat into the 

 heart of the kernel and destroy the germ. In seed corn 

 they are most effectively controlled by putting the corn in a 

 tight box, can, or bin, and setting a shallow open dish of 

 carbon bisulphide on top of the corn. This can be obtained 

 at any drug store. It evaporates quickly and the gas, being 

 heavier than air, settles down among the grains of corn and 

 kills the insects in it. Care must be taken not to breathe the 

 fumes of this gas. Large quantities of corn may be treated 

 in the same way if tight rooms can be provided. 



151. Crows and gophers often attack corn after it is 

 planted, digging up the kernels or young plants and de- 



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