Apparently, there's quite a list. Moon, shard (go figure), love, heart, mother, father, grandmother, cat, dog ... well, you get the idea. Basically, you'll be safe if you eschew (now that's a word you can feel free to use in a poem, along with switchblade) anything with a positive, upbeahttp://www.blogger.com/img/gl.link.gift connotation.
Positive, upbeat -- add those to the list of banned poetry words.
And who are these poetry police, you may ask? Well, Frank Zappa did ask, only he called them the "brain police" in one of my favorite songs when I was a Sunset Strip groupie in the 1960s ... but that's another tale. One basically told in the film Almost Famous. They didn't make the movie about me, but about some kids like my friends, only a lot less blonde and perspicacious (another word you may add to your list of approved poetry terms).
Who are the poetry brain police today? Well, check out this group for a start. Then there's always this group of totalitarians.
My point is that when writing, you should beware such arbiters of "good" and "bad" poetry. Why? Well, one example of a famous, well-published and lauded poet of his time is Robert Penn Warren. Does anyone read his work anymore? Okay, he's still got a page at the Academy of American Poets, but does anyone go there for other than academic reasons?
In fact, does anyone go to the Academy of American Poets site at all except for academic reasons?