I used to own a book on ayahuasca combinations (DMT plus an MAO inhibitor) using temperate-zone plants. I don't recall the name, and am not finding anything. Anyone know?
Phalaris is very high in DMT, but it also has a lot of toxic chemicals in it. I'm guessing you'd die if you actually tried to smoke an extraction of it, but as far as I know no one has ever actually done it. That's where the theoretically part comes in.