10 Farmers' Bulletin 819. 



Table 2. — Relative efflciency af/ainst the toMcco hudimrm of arsenate of lead 

 with different carriers. 



In experiment No. 1 arsenate of lead was used at the rate of 1 

 pound to 75 pounds of corn meal and only 0.79 per cent of leaves 

 showed injury. In experiment No. 2 the arsenate of lead was used 

 three times as strong as in experiment No. 1(1 pound to 25 pounds), 

 but with gypsum as a carrier. Three per cent of the leaves were 

 injured — nearly four times as many as in experiment No. 1. In ex- 

 periment No. 3 the arsenate of lead was used nearly five times as 

 strong as in experiment No. 1, yet the leaf injury amounted to 2.5 

 per cent — more than three times that in experiment No. 1. These 

 experiments indicate that of the three carriers corn meal is pref- 

 erable in budworm control. 



GENERAL RECOMMENDATIONS. 



At the end of the growing season tobacco plants from which the 

 marketable leaves have been removed are often allowed to remain 

 standing in the fields. These provide breeding places for the bud- 

 worm as well as other insect pests. As soon as possible after harvest- 

 ing is completed plants should be either cut or pulled up and then 

 plowed under. 



Where tobacco is grown under cheesecloth, preventive measures 

 against budworm attack may be practiced with a great deal of suc- 

 cess. In such cases care should be taken to patch all holes in the 

 cloth. Since it is necessary to provide openings in these shades 

 through which workmen with farm animals and implements may 

 come and go, gates covered with cheesecloth should be provided, and 

 kept closed as much as possible so as to exclude the moths, or adults, 

 of the budworm. 



Plants frequently are left growing within and around old seed 

 beds. These invariably are infested and contribute considerably to 

 the abundance of moths which deposit eggs on plants within the 

 fields. Plants about the seed bed should be destroyed, therefore, as 

 soon as the seed bed is abandoned. 



Seed beds should always be covered and walled in with cloth so as 

 to prevent the entrance of moths. In this way the number of eggs 

 introduced into the fields on the plants will be held to a minimum. 



Because of the nature of attack of this tobacco pest, much care is 

 necessary in direct-control practices. A slight delay in making 

 poison applications often results in great damage to the crop. 



The necessity of applying the mixture directly to the leaves of 

 the bud can not be too greatly emphasized. The effects of careless 

 manipulation may be almost as bad as if no control measures were 

 attempted. 



t 



