David and I flew to Iowa just over a week ago to see our son Tom, who has just started college there. To my surprise and pleasure, he has decided to get involved with the campus garden, and says he has blistered hands today from digging over some of the beds. I imagine that college gardens are all organic, but farming in Iowa is not.

We spent a wonderful afternoon while we were there at the Living History Farms, walking through the woodland grove where an Indian encampment, and gardens, had been created, then on to an 1850 farmstead. The third farm was from 1900, with a house that reminded me of my grandparents’ rural Iowa home. The final display was of modern agriculture, with lots of tractors and the other equipment so beloved of boys and, presumably, other visitors. It was harvest time, and we were happily, curiously examining a long bed planted with different types of soybean, and then different types of corn.

Corn is a curious plant: it depends on humans, who take its seeds out of the heavy husks, in order to reproduce. There were tall, lanky plants of the ancient grass ancestor of our modern corn, and then various other types of corn. The final one, looking not much different from its neighbor, was labeled “BT corn.” Biotech, that is, genetically modified corn. I was stunned to see it growing there, next to ordinary hybrid corn, because I thought Bt corn was always carefully separated. Insects can pollinate corn plants as far as 100 feet (31 meters) away, so the corn beside it was necessarily non-Bt anymore.

I’m not hysterically anti-GM, but I do believe strongly in the rights of consumer to know what they are eating. This experience didn’t leave me feeling quite so confident about the separation of GMO and non-GMO (yet another way of saying this). See for yourself, in this photo: biotech corn growing at Living History Farms in Des Moines, Iowa.