More bad news for vegetarians: Plants remember when you hurt them

Plants are alive — and they want to stay that way — so it may not be any more ethical to eat them than it is to eat meat. At least, that’s what I’ve argued before.

But maybe my argument didn’t convince you. Maybe you thought to yourself, “Heck, plants are alive, sure, but they don’t really feel. They don’t really think. They aren’t conscious or anything!”

Well, you’re right — so far as I know, nothing like a triffid exists on Earth (and if it did, you’d be morally obligated to kill it and eat it, murdering plant that it is).

But an intriguing survey of the available science by Olivia Judson suggests that plants do have a potent form of memory:

Previously attacked plants respond to new leaf damage more quickly. And plants that have been attacked twice are faster to respond than plants that have only been damaged once. Somehow, they remember.

The physical basis of plant memory is still being figured out. (Needless to say, it isn’t conscious memory: the trees outside your window aren’t standing there reminiscing to themselves about the great caterpillar plague of 2009.) But by now it’s clear that wild tobacco is not the only plant with the capacity for memory, nor is caterpillar attack the only stress that produces such an effect. Drought, cold and altered salt levels in the soil all do so; likewise, exposure to hostile fungi or bacteria.

If plants remember — can they also forget?

As Judson points out, helping a plant “forget” a recent drought, or priming it to be prepared for an insect pest, could have huge implications in agriculture. She also implies a comparison to the “memory” that your immune system has for infections it has already fought off.

But the lessons here are clear. If you’re a vegetarian — and I support your choice, though I don’t choose it for myself — you should make sure that you finish your plate of vegetables. No one cuts a steak off a cow, then leaves it to heal before cutting off the next steak, so why should it be any different with a plant?

After all, plants remember. And if they remember, then the next time you go looking for your rutabaga or your celery — well, maybe it’ll be waiting for you …. ready for you … lurking in your garden ….