Department of Agriculture 45 



Pyrethrum Sprays 



Some workers report satisfactory control of the stainer 

 can be secured by spraying the colonies with pyrethrum 

 sprays, using a hand atomizer. This probably is feasible 

 where the cotton foliage is comparatively thin so the colo- 

 nies of insects may be easily seen and reached by the spray. 

 With both hand-picking and with pyrethrum sprays, how- 

 ever, considerable diligence is required. The "mother brood" 

 should be eliminated, insofar as is possible. Neither method 

 is feasible after stainers become very numerous and well 

 dispersed through the cotton. 



Poison Baits 



If stainers appear in too large numbers and are too widely 

 dispersed through the cotton to permit their control by either 

 of the above methods suggested, they can usually be suffi- 

 ciently reduced in numbers by the use of a poisoned bait. 



The bait found most successful consists of a sweetened 

 water solution to which one ounce of sodium arsenate per 

 gallon of solution is added. The water may be sweetened 

 with sugar or table syrup, but black strap molasses is unsat- 

 isfactory for this purpose. Two pounds of sugar or one quart 

 of syrup per gallon of poisoned solution appeared to give 

 satisfactory results. This mixture, properly applied, will 

 prove effective in killing both adults and nymphs. 



In a series of tests with poison baits near Melbourne, Fla., 

 the only practicable method found for applying the poison 

 solution on a large scale was to. sprinkle it on the plants in 

 the form of coarse droplets. If a soluble arsenical, such as 

 sodium arsenate, is sprayed on cotton, too much of the foli- 

 age is covered, and serious damage results. Where it is 

 sprinkled on, however, the area covered is small, and the 

 plants are not injured seriously unless a large number of 

 applications are made. In practice, the "slinging" method of 

 application, described elsewhere, was satisfactory. 



If it is necessary to poison the stainer in the early fruit- 

 ing stage of the cotton, while the plants are comparatively 

 small, slinging, as practiced on large cotton, is wasteful of 

 material, as most of it will fall on the ground instead of on 

 the plants. However, two rows of such cotton can be slung 

 in such a manner that most of the material will fall on the 

 plants. The technique followed for two row slinging is as 

 follows : 



