Are we actually discussing burying plastic soon to be trash near plants so we can 'document' them? This is one of those times where I think someone solved the wrong problem.
I get it, but also plastic is fairly ubiquitous in gardening at this point. It's pretty hard to find plants that haven't spent months to years in plastic containers already. Plant labels are commonly plastic. Even soil and mulch come in plastic bags (if you buy in small, city landscape quantities).
All things in moderation.