10 MISC. PUBLICATION 4 8 4, U. S. DEPT. OF AGRICULTURE 



right and to find out the best and least costly way of using the calcium 

 arsenate dust. Cotton planters were afraid at first that the expense 

 would be so great that it would not pay to dust their cotton. They 

 know now, however, that it will pay if the weevils are seriously hurting 

 the crop and if the land on which the cotton is growing is rich enough 

 to produce one-third of a bale to the acre when there is no boll weevil 

 damage, Planters have learned also that if the dust is put on the plants 

 at the right time and in the right way a good crop will follow. 



Poison dust cannot be put on the plants in the right way without 

 proper dusting machines, which are specially built for this work. 

 There are many kinds of these machines on the market, the hand dust 

 gun being the smallest. As shown in figure 6, the man who uses the 



Figure 6. — The hand dust gun is the smallest machine for dusting cotton plants 

 with calcium arsenate to kill the boll weevil. The man who uses it turns a 

 crank, which causes a fan to blow the dust out of the long nozzle sticking out 

 of the front. 



hand dust gun walks between the cotton rows and turns a crank on 

 the machine, which causes a fan on the inside to blow the dust out 

 of the long nozzle at the front. The man who operates the machine 

 must keep the end of the nozzle pointed toward the cotton row while 

 he turns the crank, so that the dust will be sure to fall on the plants. 

 It is very hard work to operate one of these machines all day long. 

 Hand dust guns cost from $12 to $20 each, and one gun can be used 

 to dust 8 to 10 acres of cotton over the season. 



The one-mule machine is pulled by a mule or horse, which walks 

 between two rows of cotton. There are two nozzles sticking out 

 behind this machine, as shown in figure 7, and the dust is blown 

 through them onto two rows of cotton as the machine moves through 

 the field. This machine costs from $75 to $125, and one machine 

 will dust 15 to 20 acres in a single night and as much as 60 acres 

 through the season. 



The cart machine has two wheels, which straddle the cotton rows, 

 and is drawn by two mules or horses. It has three or four nozzles and 

 on one or both cart wheels a sprocket gear and a chain that drives the 



