THE TOBACCO BUDWOEM AND ITS CONTROL, 7 



are necessary in order fully to protect the bud, because the poison 

 is scattered by the expansion of the rapidly developing leaves. The 

 first two or three applications are made by means of the stick and 

 cup method (fig. 2). A quart cup with nail holes in the bottom is 

 fastened to a stick and the poison mixture is sifted upon each plant as 

 the operator walks slowly along the row. As the plants increase in 

 size the leaves of the bud are more tightly folded and it becomes 

 necessary to change the method of application by opening the bud 

 with one hand and at the same time dropping a small portion of 

 the poison mixture into the bud wdth the other hand. The poison 

 is carried in a sack fastened around the waist. (See illustration on 

 title page.) 



OBJECTIONS TO THE USE OF PARIS GREEN. 



The insecticide in use in Florida at the time of the institution 

 of experiments by the Bureau of Entomology was a mixture of 1 

 pound of Paris green to 150 pounds of corn meal. About 12 to 14 

 pounds per acre of this mixture is necessary for each application. 

 The applications must be continued from the time tobacco is set 

 until it is topped. 



Shade-grown tobacco is very tender and very susceptible to in- 

 jury from either a mechanical or a chemical source. In dry weather 

 Paris green causes very little damage, but in wet weather considerable 

 injury may result from the comparatively excessive amounts that 

 wash down and collect in the bud and in the axils of the leaves. 

 Planters are familiar with this condition and attempt to avoid in- 

 jury by making lighter applications. When such a course is adopted 

 some of the poison injury is eliminated but extra damage from bud- 

 worm attack follows on account of the insufficient dosage. When 

 Paris green mixture is used there is always the possibility of dam- 

 age either from the action of the poison on the leaves or from bud- 

 worm attack following the application of insufficient quantities of 

 the mixture. The normal injury also is increased frequently be- 

 cause some laborers apply more of the mixture than is necessary 

 for bud worm control. 



RELATIVE EFFICIENCY AND ECONOMY IN THE USE OF VARIOUS POISONS. 



Owing to this danger of injury to the leaves by Paris green when 

 used in sufficient amounts, and the imperfect protection afforded by 

 smaller quantities, the discovery of a poison that would be safer 

 under all conditions of weather and of application, and one that 

 would, at the same time, give the greatest budworm control was much 

 to be desired. During the seasons from 1913 to 1916, inclusive, ex- 

 periments were performed with at least 30 mixtures, including the 

 following poisons, some of which have been used more or less com- 



