The Cornell Report - Industry Response

[Doug Yanega]

Paul wrote:

>Doug, the industry says "Ongoing monitoring of Bt corn fields by
>companies since their introduction [three years ago in 1996] further
>shows that very little pollen lands on adjacent milkweed leaves."

This is utterly baffling. You mean to say that "the industry",
demonstrating some sort of awesome psychic prescience, has been spending
their hard-earned cash these last few years specifically monitoring pollen
deposition on milkweeds? That would be a truly mind-boggling coincidence.
WHY would they pay any attention at all to milkweeds?

>I have not personally seen the monitoring studies refered to above, but
>if they are true, how is it realistically conceivable that the Bt corn
>pollen, released for only a week or two out of the whole summer, could
>have an even a miniscule regional monarch population impact ?

A lep larva can eat an awful lot of pollen in a week, given that they spend
almost all of their time feeding, right? This is one you can figure out
easily enough, too - leaf surface area consumed per larva, then factor in
number of pollen grains per unit surface area. Besides which, I am NOT
especially concerned about monarchs. This is not just about one species.

>In other words, is it conceivable this Bt pollen dust would make a HOT
>NEW COMMERICIAL INSECTICIDE POWDER? Think of the enormous multi-million
>dollar potential uses it would have if that were true!  By gosh, if that
>were true, the chemical & seed companies would be out in the corn fields
>trying to harvest thousands of tons of the gold mine Bt corn pollen!

How much would you like to wager that now that this issue has hit the
proverbial fan, some people will not attempt to do exactly this? You are
assuming that the chemical and seed companies predicted this toxic pollen
effect before the Cornell crew reported it - and we have seen no real sign
(at least not posted here) that they *did*. Maybe the only thing that might
prevent Bt pollen becoming a new insecticide is that it might not prove
cost-effective relative to a traditional Bt treatment, nor would it be easy
to regulate. If a corn farmer can harvest his own pollen and sell it or use
it as a pesticide, that would be *against* the industry's interests, and
you can bet they'd fight it. Isn't that how these things work? It'll be
interesting to see how this unfolds.

> My guess is
>they well know whatever monarch or other non-target lep caterpillar
>tests have and will be done, they won't reveal any significant potential
>impacts on any species (at least even remotely comparable to the killing
>power of conventional insecticide sprays and dusts).

That last clause is indeed the bottom line, as I admitted before. The
proverbial choice between known and unknown devils. Again, what's your view
of a forest full of Bt-releasing aspens and/or spruces?

Peace,


Doug Yanega       Dept. of Entomology           Entomology Research Museum
Univ. of California - Riverside, Riverside, CA 92521
phone: (909) 787-4315
                  http://www.icb.ufmg.br/~dyanega/
  "There are some enterprises in which a careful disorderliness
        is the true method" - Herman Melville, Moby Dick, Chap. 82