All grist to the mill

'Cornflakes come from maize. Corned beef has nothing to do with corn. I will never again laugh at anyone for getting his grains in a twist'

Until very recently there was a man called Peter Barnard who wrote little programme trailers for the Radio Times, or at least for the small remaining part of the Radio Times that deals with radio. His programme descriptions were lively and interesting, so I was very sorry when he stopped writing. (And I was even sorrier to read in the Radio Times that it was because he had died.)

He has been replaced by someone called Jane Anderson, one of whose first jobs was to do a write-up for an edition of Radio 4's Food Programme that was devoted to maize and all such maize-derived products as polenta, which everyone pretends to like these days. Here is how she kicked off her little write-up.

"If you'd found yourself dining on polenta but a year ago," she wrote, "the likelihood would be that you'd missed the tourist bus back to Barcelona and, by accident, had stumbled across a Spanish family eating their dinner."

Now, even if you try to avoid polenta as much as I do, it's hard not to know that polenta is not Spanish. It's Italian. However unlikely it is that you miss a tourist bus back to Barcelona and stumble into a Spanish home at dinner time (you'll be stumbling around a long time, as tourist buses leave early and the Spaniards eat dinner very late), it is even more unlikely that you will find them eating polenta. About as likely as finding an Italian family eating paella. Ah – maybe Jane Anderson has actually got "paella" and "polenta" temporarily muddled up, and the Radio Times doesn't have any sub-editors who have the wit to unmuddle them.

But my childish tendency to run round the playground shouting, "Jane Anderson doesn't know the difference between polenta and paella!" is somewhat muted by the memory of my own confusions over corn. As a child, I was so used to corn in nursery rhymes ("the cow's in the corn") and poetry ("in tears amid the alien corn") and in the Bible ("Jacob saw that there was corn in Egypt") that I came to accept that corn was another kind of crop. There was wheat and barley and corn and oats...

Only gradually did it dawn on me that although I came to recognise the difference between wheat and barley and oats and even rye, I had never actually seen corn growing. Corn seemed mysteriously invisible. And this, I realised one day with a terrible shock, was because there was no such crop. Corn was only a general name for crops, or for grain or for seed. It was the name for what came out of the wheatfields, before it was turned into flour. It was the stuff that corn exchanges exchanged and that corn chandlers chandled.

Whatever it was, corn was not the name of a plant that grew in the ground. Phew – nice to get that one sorted out. And then, of course, I found that in America, corn was the name of a plant that grew in the ground, because it was the name they had given to maize, and I was confused all over again. Why the Americans changed the perfectly good Native American name "maize" to the perfectly bad name "corn" beats me, but I guess it was for the same reason that they gave the name "robin" to American birds that were nothing like robins at all.

And finally, I know that cornflakes come from maize and that corned beef has nothing to do with corn, but all to do with being preserved in salt, and that cornpone is cornbread, "pone" being the Algonquin word for bread, and that "pone" can also mean the player to the dealer's right who cuts the cards, and now that I think I have got my crops sorted, I will never again laugh at anyone for getting his grains in a twist.

Except Mark Lawson.

The other day, on Radio 4's Front Row, Mark introduced a piece on the new Mel Gibson film Signs by saying that it was all about crop circles, "those patterns we sometimes get in the hay". Hay? Crop circles in hay? Oh, dear – it's very hard not to run round the playground shouting, "Mark Lawson's a townie who doesn't know the difference between growing wheat and dried grass – no wonder a quarter of a million people had to go marching in London!"