10 FARMERS BULLETIN 872. 



crop free from weeds and grass, during the growing season not only 

 tends to increase the yield but also destroys hiding places of the 

 moths. 



POISONING CORN. 



Unfortunately no very satisfactory method of poisoning the worms 

 on corn has been devised. As many as 50 per cent may be destroyed, 

 but the remainder will gain- entrance to the ears and produce the 

 usual injury. Eecent work conducted in Kansas by 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 

 the}^ 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 lorobably would more than offset the advantage 

 gained under field conditions, and this method will be more appli- 

 cable in protecting sweet corn or corn grown especially for roast- 

 ing 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 bollworm injury 

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

 ravages of the boll weevil. No loss of money or energ}^ results from 

 putting such cultural practices into effect, even though the bollworm 

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



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 

 Avhen 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 

 varieties which make comparatively small stalk without a super- 

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

 of the bolls after they are grown. The early and complete destruc- 

 tion of cotton stalks as recommended for the boll weevil will prevent 

 the maturity of many late bollworms and destro}^ a considerable 

 number outright. 



