BOLL WEEVIL. 11 



siderable amount of commercial fertilizers, while in Louisiana little 

 or no fertilizers need be used. 



The above explanation is made in order that the people of South 

 Carolina may not feel that there are any special conditions of soil 

 or climate that can be expected to make the boll-weevil problem in 

 this State less serious than it has been in other States. As a matter 

 of fact, when the fertilizer situation is considered, Georgia and 

 South Carolina are liable to suffer greater loss than any other States 

 thus far invaded. In South Carolina an additional danger lies in 

 the attraction which the cotton mills hold out to the family of the 

 small farmer. 



METHODS OF CONTROL. 



Through heat and sunshine, ants, insect parasites, birds, and the 

 crushing effect of the injured square on the eggs and larva nature 

 keeps up its warfare against the boll weevil. 



1 echnical investigations are still on the way, and while soil build- 

 ing and agricultural operations may always he expected to he funda- 

 viental in producing a cotton crop under weevil conditions, experi- 

 mental work of recent years has shown that the holl weevil can he 

 poisoned with profit whenever conditions are favorable for this worh 

 and correct methods are employed. Unfortunately during 1920 and 

 1921 the weather conditions in South Carolina- were extremely ad- 

 verse for poiso7iing and generally no profitable results were secured. 

 The evidence at hand from other States would indicate that boll- 

 weevil poisoning in South Carolina would he profitable on good land, 

 with more favorable weather conditions than those of 1921, and pro- 

 vided that poisoning is correctly done. The Delta Laboratory, Tal- 

 lulah, La., which has been chiefly instrumental in developing the 

 poisoning method to its present status, makes the following recom- 

 mendations : 



HOW TO POISON. 



Use only pure calcium arsenate in the form of a dry powder. Ap- 

 ply this in the dust form. 



■ Purchase this to conform to the following specifications : 

 Not less than 1^.0 per cent of total arsenic pentoxid. 

 Not more than 0.76 per cent water-soluble arsenic pentoxid. 

 Density not less than SO or more than 100 cubic inches per pound. 



Have your county agent send a sample of your cal^cium arsenate to 

 the Delta Laboratory, Tallulah, La., for free analysis, to make sure 

 it is satisfactory. 



Use orily dusting machinery especially constructed for cotton dust- 

 ing. 



Poison only tvhen the air is calm and the plants are moist. This 

 practically mean^ only night applications. 



Use about 5 to 7 pounds of calcium arsenate per acre for each 

 ■application. 



Start poisoning when the ■weevils have punctured from 10 to 15 

 per cent of the squares. 



Keep your cotton thoroughly dusted until the weevils are under 

 control. TJiis usually means about three applications at the rate of 

 one every four days. 



