aloe 
Derris and cube dusts prove effective against tobacco flea beetle.-- 
Fe Se Chamberlin, of the Quincy, Fla., laboratory, reports as follows; 
"Preliminary tests performed last season indicate tmt derris and cube 
dust offer much promise as control agents against Epitrix parvula Fabe . 
on shade-grown tobaccoe A series of experiments with these poisons 
was carried out_on plant beds during March and April. Tobacco dust and 
kaolin were used as diluents. Both derris and cube dusts containing 
1 percent rotenone gave good control in light infestations. No heevy 
infestations were available for treatment. Neither poison caused ine 
jury to the foliage, even when applied in the undiluted forme Plant 
beds: in this region are very susceptible to polson injury and all 
materials tested in the past have caused some damage when applied under 
certain conditions." 
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ing the proper time.interval between the cessation of applications of 
poisonous insecticides to celery and the time of harvesting in order to 
avoid harmful residues on the market product, Ce Fe Stahl, of the Sanford, 
Fla.e, laboratory, tagged new leaves of celery plants at weekly intervals 
in celery plantings made during October, November, and December 1944e 
The last of these tagged plants were harvested on April 9, 1934. The 
,age of the oldest leaf remaining upon .individual. celery plants when the 
celery was sent to markdt ranged from 35 to 49 days in the three princi- 
pal plantings, and in the two principal celery-growing districts of the 
Sanford sections Although the average age of the oldest leaves remain-=- 
ing on the market product ranged from 43 to 49 days, it is apparent that, 
in order to insure a proper margin of safety in the quantity of insecti-~ 
cial residues on the market product, arsenicals should not be applied to 
celery plents within a period of 7 weeks prior to harvest, under condi~ 
tions existing in the winter growing of celery in the South. 
Similar studies are being conducted with other crops, such as cabs 
bage, lettuce, and spinach, but data on these crops are not yet available, 
Spotted cucumber beetle larvae found feeding on cabbage leaves.-~ 
C. BE. Smith, of the Baton Rouge, La., laboratory, reports that while making 
routine examinations of cabbage.plants on his experimental plots many 
nearly full-grown larvae of Diabrotica duodecimpunctata Fab, were observe 
ed feeding on leaves of cabbage that had been covered with soil. during 
cultivation. Many of these larvae were of a decided greenish color, ate 
tributable to their feeding on the green leaves of the cabbage. This 
rather unusual observation seems worthy of note, as larvae discovered 
feeding under such circumstances might easily be mistaken for other spe 
C1ieS. : 
Addition of molasses in cutworm baits may improve physical qualities,-- 
He H. Richardson, of the greenhouse insect laboratory, Washington, DeCe, 
in his recent studies on thé use of a mixture of molasses, water, and 
peris green for the control of tnrips has found that the addition of mo- 
lasses frees a greater quantity of arsenic in the mixture than is the case 
