Something I have noticed a great deal lately in the poetry world, which is to say in the journal "Poetry" founded in 1912 by Harriet Monroe where I get most of my poetry of late, is a growing trend of citing your sources. That is to say, when a young poet steals a line from one of their elders or contemporaries, they will put a little note at the bottom of the page saying, "the part about eating cheese comes from May Swanson's famous poem 'A Canticle for Cheezybits" or "the form of this poem was invented by Julian Barnes in 1976 to make fun of his college roommate but I am reclaiming it here for serious use" or "several of the nouns in this poem were also used by Denise Duhamel in her double sestina 'Incest Taboo.'"
Sometimes they will even make a little note if the thing is a perfectly normal phrase that anyone might say by accident, like "green sorrow" or "underwear parade." Or they will say, "the idea of writing a villanelle about onions was suggested to me by the multi-author Onionelle series published in Old Hickory Review November 1983."
I expect this is just a nice way of giving credit where credit is due and that young people are inclined to be polite than the people of my generation. In addition, due to living in a time of overwhelming uncertainty, they may have a preference for knowing where their poetry came from just as they prefer to know the complicated and heartwarming origin stories of their plant-based meat substitutes and their clothing, the past being proverbially more stable than the future.
However harmless it may be in intent, I worry a little about this trend. It's not just that as a reader I enjoy the fun of recognizing unmarked allusions to other poems, tv shows, and so on, and would prefer not to be led around by the hand, though I admit that was the first objection that came to mind when I began to notice these notes. But there are others to consider, too. Suppose it becomes so much the norm that anyone who neglects to make this kind of accounting is branded a plaigiarist? even if, as must inevitably happen, they simply happened to think of the same three words together as some other person?
Does citing one source mean that you are committing to cite every possible reference made in your poem? I don't think this is possible. However, after citing one or two sources, a poet may find themself at the receiving end of angry letters saying, "You failed to credit me for the idea of putting the lines in two columns, as seen in my poem in Free Lunch Summer 1978" or, "I also began two lines in a row with the word "blue," yet I saw no acknowledgement from you in your recent "Blue Stakes Blueblood" poem excerpt." Worse yet, rumors of failure to acknowledge and of plagiarism may spread indirectly through the many "grapevines" produced by public whispering.
What worries me the most is simply that there is no way to keep track of what words came into your head and where and when. I myself have been in the position of making what I thought was a straightforward comment out of my own head, only to be told I was quoting from a movie I had never seen. There are only so many letters in the alphabet and some of them don't even sound like anything if you mash them together.
Poets of the world, do you credit your influences whenever you publish a poem? Editors, do you expect that allusions, borrowed lines, and other influences will be cited in the text?
As I have yet to publish in an official capacity (with one notable but obscure exception), I have not given much thought to this question. In the comfort and security of my own personal web page, I will probably continue to let my influences flow as naturally through my fingers as the world itself, given that they are as much as trees and birds and so on, part of the world I inhabit. That is, I would not expect a poet to add a note saying "I got this line from a poem I read the other day" any more than I would expect them to feel obligated to note, "I got this bird from a bird that landed on the dumpster outside my window." But maybe you will say that we owe each other more elaborate deference than we owe to birds. But to that I would probably say that birds are also part of each other.