One of the frequently expressed concerns in the Desert Garden is: "I have ants eating my plants." And the standard response, delivered by myself and others with perfect confidence, is: "Don't worry, the ants aren't really eating your plants; they are on your plants but not causing any damage. Ants don't eat plants."
Guess what? I have ants eating my plants.
My eggplants, to be specific. Not being at first certain that they were really doing what it looked like they were doing (cutting stems, severing leaves, drilling holes in the eggplant fruits), I hunkered down and watched them for the better part of an hour.
I have ants eating my plants.
If you click to see the enlarged version of the picture above, you can see the ants clustered at the terminal shoot of one of my eggplants; the leaf towards the back has been mostly severed and will shortly shrivel up and die. I collected samples of the ants and forwarded them to the Bugman at the University of Arizona, Carl Olson, and I'll let you know what he has to say about the type of ant this is.
Ants, as a general rule, don't damage plants. This bunch apparently didn't get the message.