Mike, you don't say why you want to suck up excess nitrogen, but what came to mind for me was a Gabe Brown
video where he talks about using forage radishes to sequester nitrogen for future crops. I can't remember which video it was, but here are a couple of articles that say the same thing.
"Radish cover crop traps nitrogen; mystery follows" at Phys.org
This second one addresses a number of plants, including radishes.
"Nitrogen cycling and cover crops" at FarmProgress.
I don't know if that's what you're looking for, but I hope it helps!