CORN INSECTS 217 



times the larv?e desert the ear when only partly grown and mi- 

 grate to other ears on the same or nearby plants. In the cotton 

 belt the later broods of caterpillars produced after corn has 

 become hard are to be found mostly on cotton. In Iowa and 

 Nebraska, late brood caterpillars have been found on alfalfa 

 and clover. 



Control. 



No practical method of controlling the corn ear-worm on 

 field corn has yet been discovered. Experiments in New 

 Jersey have shown that the injury to sweet corn may be greatly 

 decreased by dusting the silk with a mixture of 50 per cent 

 powdered arsenate of lead and 50 per cent finely ground sulfur. 

 The first application should be made soon after the silk appears, 

 followed by one or two others before the corn is ready to pick. 

 Dust can be applied most conveniently by means of a small 

 hand bellows carried under the arm and equipped with a piece 

 of rubber hose about two feet long attached to the outlet by 

 which the dust is directed downward into the tip of each ear. 



When sweet corn is grown for the cannery, early planting 

 is advisable, but cannot be practiced when corn is grown 

 for the market because for this purpose a succession cover- 

 ing as long a period as possible is required. Much benefit 

 may be derived from fall or winter plowing land on which an 

 infested crop has been grown in order to destroy the pupte. As 

 large an area as possible should be included in this treatment 

 as the moths are capable of flying a considerable distance. 



The injury to tomatoes may be in part prevented by spraying 

 the vines with arsenate of lead (paste), 4 to 6 pounds in 100 

 gallons of water, making one or two applications before the 

 fruit is half grown. Later applications are likely to stain the 

 fruit. Injured tomatoes should not be left in the field but 

 should be picked along with the others, sorted in the packing- 

 house and should then either be buried or dumped into a pond. 



