-78- 
Qn hairy vetoh in Oregon two applications of a 6-percent DDT dust 
at rates of 22 to 25 pounds of the dust per acre as the pods began to 
set and 15 days later gave excellent control of the vetoh bruohid with- 
out risible injury to tiie plants, and were eignifioantly better than 
two applications of a dust containing 1 peroent of rotenone at approximate- 
ly the same rates per acre.— Packard (28 5) * 
Bruchus plsorum (L«), the pea weeril 
In laboratory experiments at Moscow, Idaho, in 1943, relatively low 
mortalities of the pea weevil were obtained with a 10-«peroent DDT dust 
when the weevils were transferred from treated cages to clean cages 5 
minutes after treatment* Later tests showed that the mortality could 
be increased by retaining the insects in the treated cages for a longer 
time* In 1944 field experiments were oonduoted on plots 24 feet wide 
and located end to end around the edges of large fields of peas grown for 
seed* In 21 replicates a 5-peroent DDF dust reduoed the adult pea 
weevil infestation 99 peroent in 2 days, whereas a 0*75-peroent rotenone 
dust reduced the infestation 98 peroent in a like period* In these tests 
the insecticides were applied with a power duster at the rate of 30 pounds 
of the DDT dust mixture and 20 pounds of the rotenone dust mixture per 
acre* In 7 replioates 2*0 peroent of the dried peas in the DDT plots 
were weevily as compared with 2*7 peroent in plots where rotenone dust 
was used*— *!hite (375- )* 
The pea weevil was controlled by eight applications of 5-percent 
DDT in light summer cpray oil, average about l/2 gallon per aore, with 
a hand atomiier from June 6 to August 1*— Gray (188 ) * 
Byturidae 
Byturus tomentosus F*, the raspberry fruitworm 
In England a laboratory preparation of DDT (75 peroent p-p f compound) 
oontaining 0*05 percent of Agral 2 and 0*025 peroent of sulfite-lye, and 
two proprietary preparations were tested* The proprietary preparations 
were not exactly alike* In 1945 a product of Swiss origin was used* This 
contained 5 peroent of 3DT on a base consisting of chalk and bentanite, 
together with a wetter of the Hekal type (an alkyl naphthalene sulfonate) • 
It settled out from suspension so rapidly that its use in this trial was 
possible only beoause of the very efficient agitation available in the 
spraying machine* In 1944 a British product was used which also oontained 
5 peroent of DDT (77 percent p-p» oompound). However, the DDT in this 
product was on a base of china clay with some bentonite, together with 
alkyl naphthalene sulfonate and a dinaphthylm ethane sulfonate as auxiliaries* 
DDT at 0*025 peroent or at 0*05 pereent gave as good oontrol as a 
Lonohooarpus spray oontaining approximately 0*011 peroent of rotenone. 
