10 Farmers' Bulletin 872. 



usual injury. Eecent work conducted in Kansas b}^ Mr. J. W. 

 McCulloch and in Missouri by Mr. Leonard Haseman indicates that 

 the application of powdered arsenate of lead to the silks as soon as 

 they begin to appear will reduce the injury considerably. Owing to 

 the rapid growth of the silk and the fact that the eggs are deposited 

 continuously, it is necessary to make a light application of poison at 

 three or four day intervals to secure good results. In the experi- 

 ments mentioned the poison was blown onto the ears with a dust gun 

 or applied by hand with a cheesecloth bag. The cost of application 

 and material probably would more than offset the advantage gained 

 under field conditions, and this method will be more applicable in 

 protecting sweet corn or corn grown especially for roasting ears, 

 and in reducing the amount of injury to special selections grown 

 for seed purposes. 



CONTROL ON COTTON. 



CULTURAL PRACTICES. 



Several of the measures best calculated to reduce boll worm injury 

 in the cotton-growing States are equally effective in checking the 

 ravages of the boll weevil. No loss of money or energy results from 

 putting such cultural practices into effect, even though the boll worm 

 should not appear in very destructive numbers in any particular jeRV. 



To protect cotton from bollworm injury it is important (1) that 

 early maturing seed be selected; (2) that the crop be planted as 

 early as is consistent with getting a good stand and having the crop 

 start off well; (3) that poor lands be fertilized and. cultivation be 

 thorough and frequent. Every step should be taken which will 

 hasten the early maturity of fruit and keep the plants in a healthy, 

 growing condition. The reason for this can be seen readily when 

 we know that the bollworms pass to the cotton when the corn becomes 

 mature, and that hard bolls are not subject to injury. Since the 

 moths hide in the foliage when the growth is luxuriant, those varie- 

 ties which make comparatively small stalk without a superabundance 

 of leaves are desirable. This also hastens the drying out of the 

 bolls after they are grown. The early and complete destruction of 

 cotton stalks as recommended for the boll weevil will prevent the 

 maturity of many late bollworms and destroy a considerable num- 

 ber outright. 



POISONING COTTON. 



The use of poisons against the bollworm has met with considerable 

 success when the poisons have been applied at the proper time. 

 Attention has been directed to the fact that a large proportion (from 

 60 to 80 per cent) of the eggs deposited in cotton fields are placed 

 elsewhere than on the squares and flowers. Following hatching, 



