14 MISC. PUBLICATION 484, U. S. DEPT. OF AGRICULTURE 



calcium arsenate may be used as a dust or as a liquid. If dust is used 

 only 3 to 4 pounds to an acre are needed. The liquid poison most 

 often used is a mixture of 1 pound of calcium arsenate, 1 gallon of 

 molasses, and 1 gallon of water. This sweetened poison is smeared 

 on the top of the plants with a mop made by tying a rag around the 

 end of a stick. The mop is dipped in a bucket of the poison and is 

 pushed through the top of the plants as the worker walks along. A 

 little of the mixture is thus smeared on the leaves and stems. Mop- 

 ping should be done during the day when the plants are dry, so that 

 the weevils will drink the sweetened poison. 



Many growers often waste money by putting poison on the plants 

 early when there are no weevils. But when there are very many 

 weevils, dusting or mopping should begin when the first squares are 

 just large enough to be seen. If there are still a lot of weevils, another 

 dusting or mopping should be made in 5 to 7 days. After two or 

 three of these treatments the squares are usually big enough for the 

 weevils to puncture and then mopping is no longer of any use. 

 Mopping costs a little less than dusting, it can be done at any time of 

 the day, and it requires no dusting machines. 



The use of poison before the squares form helps to cut down the 

 number of weevils early in the season, but the plants will usually have 

 to be dusted with calcium arsenate after the squares form if the 

 weather has been favorable for the weevils. Even though early 

 treatments are used, growers should not depend on these alone to con- 

 trol the weevils. The cotton should be examined often, and if 10 

 percent or more of the squares are infested before a full crop of bolls 

 have set, the plants should be dusted. 



OTHER WAYS OF DESTROYING THE BOLL WEEVIL 



The farmer ma}^ fight the boll weevil in many other ways besides 

 using calcium arsenate. Sometimes it will not be necessary to go to 

 the expense of poisoning if other methods are used. One of the most 

 important is to cut down the cotton plants early in the fall. At that 

 time there are likely to be many young weevils in the squares and 

 bolls that are still on the plants. If they are left in the fields, the 

 weevils will grow into adults and then go into their winter sleep. 

 Those that live through the winter will attack the young cotton plants 

 the next spring. To prevent this, all the cotton plants should be cut 

 down or completely plowed up as soon as possible after the crop has 

 been picked. If the cotton stalks are destroyed early in the fall, the 

 food of the adult weevils will be taken away and they will go into their 

 winter sleep hungry. Weevils weakened by hunger are less likely to 

 live through the winter. To kill many weevils, the stalks should be 

 destroyed before the first killing frost. 



If the fields cannot be cleaned up before frost time, it is often a good 

 thing to pasture them with livestock, letting the animals eat as much 

 of the plants as they will. Even if poison has been used earlier in the 

 season, not enough of it will stay on the plants after two or three rains 

 to hart the grazing animals. 



Since the weevils use any kind of grass or weeds for winter shelter, 

 it would be well to clean up around the edges of the cotton fields, 

 along fence rows, and in all the ditches on the farm. If this is done 

 thoroughly, many of the weevils will be killed by the cold. 



