I was wondering about publishing on the web in particular. Is something written on a blog, for instance, free for the taking?
You can't cut and paste something from a website and use it.
Ok, we all do it.
In fact, I did it below with the Caterpillar poem.
I didn't pass it off as my own, but still, it's a violation of copyright to do it.
Robert Bly probably isn't coming after me with a writ of seizure for my gin bottles and expensive poodle but he'd be within his rights to call me up and say "cease and desist, sister, if you know what's good for you". A snarl would probably accompany the threat.
Why won't he? Well, he's probably got better things to do, and he might actually think that posting the poem would be a good thing, and besides...he'd be hard pressed to prove actual damages.
That's the rub. Copyright is a civil matter not criminal. They don't haul your sorry ass off to jail for posting poems, they send the accountants and ask if you made any money, or cost them any money. If the answer is no to either or both, you're likely to get off scot free as a practical matter.
Morally of course, you're going to Hell. But that's ok, you can sit here next to Miss Snark, Mick Jaggar and David Bowie in the smoking section.