6 CIRCULAR 639, U. S. DEPARTMENT OF AGRICULTURE 
After it is mixed, the bait should be applied within 48 hours at the 
rate of about 1 pound (dry weight) per 100 square yards of plant- 
bed surface. It may be scattered broadcast over the entire bed if 
the application is being made prior to the germination of the seeds. 
After germination or the appearance of the plants above ground, the 
bait should be scattered between the rows, and extreme care should be 
exercised to avoid throwing any of the particles on the plants them- 
selves or on the areas in which the seeds are planted. If this precau- 
tion is not taken, severe burning of the plants may result. 
For the best results, applications should be made as late as possible 
in the afternoon, and at a time when the surface of the soil has been 
moistened thoroughly by recent rainfall or by irrigation. The num- 
ber of applications necessary will vary with local conditions and the 
abundance of the pest, but on the average two applications spaced 
several days apart should give satisfactory control. 
CAUTION: Bait containing calcium arsenate or paris green is poisonous, 
and care should be exercised to keep it away from poultry and domestic 
animals. 
FLEA BEETLES 
The tobacco flea beetle (E'pitrix parvula (F.)) is frequently found 
in tobacco plant beds, but seldom causes severe injury to the seedlings 
in this region. In some instances, however, these insects are suffi- 
ciently numerous to necessitate control measures. Occasionally the 
potato flea beetle (A'pitrix cucumeris (Harr.)) is found also attack- 
ing young tobacco plants in seedbeds. 
Injury in beds usually begins around the margins and may spread 
over the entire area. If the infestation occurs when the plants are 
small, those fed upon may be completely destroyed. Feeding on the 
larger plants stunts and delays their growth. 
Flea beetles can be controlled in tobacco plant beds by applying a 
dust containing 1 percent of rotenone at the rate of 8 ounces per 100 
square yards of plant bed. Either a home-mixed or a commercially 
prepared dust may be used. Directions for preparing a home-mixed 
dust are given on page 28 of this circular. 
Clay and finely ground tobacco dust are used as diluents in com- 
mercial brands of derris and cube dust. Both these diluents are 
satisfactory for use on tobacco plant beds. If tobacco dust is used 
it should be certified by the manufacturer as being sterilized and 
free from pathogenic organisms which might produce tobacco dis- 
eases. An efficient rotary, hand-operated duster should be used to 
apply the poison mixture to the plants, and coverage should be as 
uniform as possible. One or two applications of the dust are usually 
sufficient to control the limited infestations of flea beetles that attack 
the plant beds in this region. 
CuTWORMS 
Although cutworms are injurious mainly to newly set tobacco, they 
frequently cause some damage in the plant beds. Young larvae eat 
small portions from the tobacco leaves, while the large worms may 
destroy whole clusters of small plants. In spite of board and log 
barriers at the edges of beds, cutworms often work their way in from 
surrounding areas. Infestations are usually confined to the margins, 
but they may extend over an entire bed. 
