Department of Agriculture 21 



The amount of material used is governed by the size of the 

 mop, and the frequency with which it is dipped. When the 

 cotton is small, a comparatively small mop should be used, 

 so as to apply about a gallon to one and one-half gallons of the 

 mixture per acre. As the cotton increases in size, larger mops 

 should be used. Towards the end of the mopping season, about 

 two gallons of mixture per acre are used for one mopping. 

 The average for the season should be about a gallon and a 

 half of mixture per acre per application, or an average of one 

 gallon of syrup and one pound of poison per acre per applica- 

 tion. 



In case a light shower occurs an hour or so after the mop- 

 ping is completed, the plants should be examined to see if any 

 considerable quantity of the poison was washed off. If it was, 

 it should be reapplied as soon as the plants are dry. If, how- 

 ever, no rain occurs inside of three hours, reapplication of 

 the poison is not necessary unless the cotton is known to be 

 heavily infested with weevils. 



The seven-day time interval for mopping is based on a 

 knowledge of life history of the over-wintered weevils. As 

 was explained earlier, over-wintered weevils do not begin to 

 deposit eggs immediately upon entering the cotton field, but 

 must feed for about a week before eggs mature. It is safe to 

 allow over-wintered weevils to remain in the field five or six 

 days, therefore, for during that time no new brood will be 

 started. If they are allowed to remain in the field more than a 

 week, however, eggs will be deposited in the squares, and a 

 new generation of weevils will have to be dealt with after the 

 over-wintered weevils are killed. Growers from time to time 

 have skipped a week during the poisoning season, thinking it 

 would make but little difference, only to find that it was nec- 

 essary to make several poison applications later in the season 

 in place of the one missed, in addition to going to considerable 

 trouble to pick up fallen weevil-punctured squares. 



After the end of the mopping season and during the latter 

 part of June and the first part of July, a careful examination 

 of the field should be made from time to time for any weevils 

 that might have been, for one reason or another, missed by 

 the poison. Where an infested spot is found, the spot should be 

 "flagged" by sticking up a marker. All punctured squares 

 should be picked up and burned and the infested area should 

 be poisoned by a method described later as "slinging." 



