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A highly publicized study out of Cornell University, which showed that pollen from genetically modified corn can harm monarch butterfly larvae, has focused attention on America's most popular insect. While the study offered little new knowledge, it has stirred the emotions of nature lovers everywhere.

The best thing that could happen from the publicity would be that we'd become a nation of Johnny Milkweeds, planting milkweed seeds wherever we can (but not near cornfields). Milkweed is the only food of monarch caterpillars, and it is not as plentiful as it used to be.

Anti-technology activists are hoping the study will lead to a ban of genetically modified corn, which contains a bacterial gene that wards off harmful insects. But this could actually harm monarch butterfly larvae and other insects by forcing a further reliance on broad-spectrum insecticides.

I bet that many more monarch butterflies are killed by automobiles than will ever be harmed by pollen from Bt corn. The reason is obvious to anyone who spends much time in and around cornfields, as I have. There is practically no milkweed there to attract the monarchs.

I have walked hundreds of Indiana cornfields over the years, and can't remember the last time I saw monarch caterpillars on milkweed. But on the interstate between Lafayette and Indianapolis, I've seen monarchs pressed into the grill of a semi.

I developed an interest in entomology when I was a boy in Kansas. hoeing sunflowers out of my father's cornfields. I was moved by the beautiful tiger-striped caterpillars I saw on the milkweeds in the fields. Today, I don't see monarchs in cornfields because I don't see milkweeds. Farmers have learned how to get rid of these plants.

There are two lessons from this. First, if the monarch is declining in numbers, it is partly because milkweed has declined. More important to the issue at hand, if there are few milkweeds in and around cornfields, there is little danger that pollen from Bt corn will fall on milkweeds and harm monarchs. The answer is to replace the lost farmland milkweeds with milkweeds in safer places.

The monarchs' situation is similar to that of the eastern bluebirds, which were in serious decline because they nested in cavities of dead trees or hollow fenceposts. With the clearing of woodlands and conversion to metal fence posts, bluebirds were in trouble. America responded with a massive effort to place bluebird houses.

The birds are back. Several nest on my 80-acre hobby farm. The same can be accomplished for the monarch. With roadside mowing and agricultural weed control, the milkweeds have declined. But they can be returned rapidly. I've planted milkweeds on the dam of my pond. which I never mow. And there are countless other places, urban and rural, where they can be planted.

Many school groups have been planting milkweeds to attract monarchs. While they are a yield-robbing pest to farmers, they are attractive flowering plants in the right setting.

We need more data before we can adequately assess the issue of pollen and monarchs. The Cornell experiment provided no information beyond what scientists already knew - that if you can make a caterpillar eat enough Bt pollen, it will die. But how much is enough, and how likely is a monarch arch to encounter a harmful dose?

Aside from basic toxicology studies, the next thing we need to learn is how many monarch-bearing milkweeds are within the range of corn pollen. If monarchs aren't there, they won't eat pollen. I believe that when we really start looking. we will find the number to be very low. The risk to monarchs is far too low to justify restricting this new technology.

Dr. Turpin is a professor of entomology at Purdue University in West Lafayette and is a past president of the Entomology Society of America.

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