-5- 
All sprays were applied weekly at 100 ml. (3 fl. oz.) per 1,000 cubic 
feet of air space. The tobacco moth was controlled with a spray con- 
taining 0.2 percent of pyrethrins in a light volatile oil. Spraying was 
more effective, cheaper, and less objectionable than dusting with 
pyrethrum powder. It was also more effective than two atmospheric 
fumigations during the season with hydrogen cyanide, and was substan- 
tially cheaper. 
Development of cigarette beetle populations was retarded by a spray 
containing 1 percent of pyrethrins in a light volatile oil. A light in- 
festation of this insect was controlled as effectively with the sprays as 
with two fumigations with hydrogen cyanide, and much more cheaply. 
Where a heavy infestation had already developed, however, the spray was 
less effective than three fumigations with hydrogen cyanide, and gave 
inadequate control in some instances. 
Although beneficial, the spray program did not keep the infestation 
so low in unscreened warehouses as in screened ones. 
In 1948 pyrethrum-oil spray was applied in 81 screened, closed-type 
warehouses containing over 120 million pounds of flue -cured tobacco 
without any observed effect upon the taste, aroma, texture, or aging of 
the tobacco. 
Literature Cited 
(J.) Reed, W. D., and J. P. Vinzant. 
1942. Control of insects attacking stored tobacco and tobacco 
products. U. S. Dept. Agr. Cir. 635, 40 pp.,illus. 
(2) Tenhet, Joseph N. 
1946. A power sprayer for applying concentrated insecticides. 
U. S. Bur. Ent. and Plant Quar. ET-231, 4 pp., illus. 
/Processed]/ 
(3) 
1947. Pyrethrum-oil sprays in open-type tobacco warehouses. 
U. S. Bur. Ent. and Plant Quar. E-717, 5 pp. /Processed_7 
