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Tvro methods are used in applying the rotencne dust. 
In large-scale ccrmercial pea grovdiig it is applied vdth 
a povrer duster that covers about 30- feet at a svjath. In 
small garden plantings the dust is applied directly to 
the roviTS of peas vath a hand dust gun. The first dusting 
on garden plantings is made just after the peas come into 
bloom and an application is i:iade in each of 3 weeks there- 
after. In large field plantings the dust is applied at 
the rate of 20 pounds to the acre, For a garden planting 
the entomologists advise dusting at the rate of about 1,05 
ounces of dust to 100 linear feet of peas, ' " 
Dr, Wakeland reports that in the cannery pea districts 
of Washington and Oregon about 30,000 acres of peas were 
protected by border dusting. One grower protected 4,000 
acres of peas mth the dust, 
Brindley (49) in 1S37 reported that rotenone dusts gave promise in 
control of the pea weevil. As a result of large-scale field tests during 
1936, dust mixtures containing 1,0 or 0,5 percent rotenone, vdth finely 
ground diatomaceous earth, tobacco dust, or sulfur as diluents, reduced 
the irifestaticn more than 99 percent, on an average, in green peas harvested 
ftor canning and in dry peas harvested for seed or processing, as compared 
■vdth tlie pea rreevil infestation in untreated plots. These dust mdxtures 
gav? results superior to treatments -/dth undiluted cryolite, calcium 
arsenate-sulfur (1:5), or Paris green-lime (1:5), Five treatments were 
applied to these experimental plots at a dosage of 20 pounds per acre per 
application, vdth the exception of the plot treated with the dust mixture 
containing 0,5 percent of rotenone in diatomaceous earth, vyhich received 
40 pounds per acre per application. In the untreated plots, on an average, 
approximately 43 percent of the peas v/ere infested by the pea vreevil , 
Brindley, ChajTiberlin, and Ascociates (_52) in 1937 reported that 
dust mixtures containing rotenone have given excellent control of the 
pea v/Gcvil in recent large-scale field tests in Idaho, ViTashington, and 
Oregon, Talc appears superior to diatomaceous earth as a diluent. In 
the Dayton, Wash,, area many tons of rotenonc-dust mixtures have been 
applied to the Y/eevil- infested peafields. In most instances a dust 
mixture containing 1 percent of rotenone has been applied to strips 20 
to 30 feet wide around tiie edges of the field, v.ihere the hibernating 
weevils have congregated. Under favorable vreather conditions, most of 
the infestations in ihe treated fields have been reduced more than 95 
percent and in some instances the v/eevil population has been reduced 99 
percent. From one to three applications to those field borders have been 
necessary, depending on the movement of the v/eevils into the fields after 
such fields have- been dusted, 
Howard and I.ason (l98) in 1937, in discussing tlie best rotenone con- 
tent of dusts for general'""use on the truck fai-m or in the garden, stated 
that it may be necessary to use a 1-percent dust in the control of the pea 
weevil. 
