One fifth of a thimble per acre

Paul Cherubini cherubini at
Mon Nov 13 17:45:45 EST 2000

Patrick Foley wrote:
> Paul,
> You seriously want to claim that aerial spraying [for mosquitoes]
> kills only the target species?
> Let's not argue about the obvious.

Yes Pat, aerial spraying for mosquitoes, while devastating to
mosquitoes (for a week or two)  is not typically devastating 
butterflies because of the extremely small dosage of insecticide used:

The info.below was copied from

"The product name of the mosquito adulticide used by the 
Project is called Scourge. It is a combination of two ingredients,
resmethrin and piperonyl butoxide. Resmethrin is a synthetic
pyrethroid, and piperonyl butoxide is a synergist (a chemical that
enhances the ability of another), allowing resmethrin to control the 
adult mosquitoes at a lower concentration. Scourge is mixed with
a soybean oil, which is used as a carrier. The ratio of soybean oil 
to Scourge is 4.5:1. It is sprayed from the truck at 3 ounces per minute, 
at a vehicle speed of 10 miles per hour. This works out to
0.5 ounces of Scourge and oil per acre. The actual amount of resmethrin
sprayed over a one acre plot is approximately equal to one fifth of a
thimble, or about 10 to 15 drops from an eyedropper.
This presents a minimal risk to humans, pets and non-target 
species. The active ingredient in Scourge photo-degrades (breaks 
down in sunlight) in less than four hours."

The same phenomenon takes place in many public restaurants,
grocery stores and johns. Battery operated dispensers spray an 
invisible mist of pyrethoid insecticide (like resmethrin) every 15 
MINUTES at a dosage sufficient to kill houseflies, but not larger 
insects like butterflies or even drosophila. The dosage is so low 
restaurant patrons do not  realize they are being sprayed every 
15 minutes.

Paul Cherubini


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