As http://www.wtfcomics.com/ has a troll shammy named after a herb, how about anything from the list at http://www.motherherbs.com/herbs-by-common-names.html - a lot of those sound like something a Troll might be called...
I used Aknot once. He was the Mangalore leader in the movie "The Fifth Element". they would pass more for trolls, but it worked.