Pel-tar'uk was a type of plant found on the volcanic plains on the planet Vulcan.

They were low-lying bright green shrubs which produced small olive-green berries that were edible by Vulcans and Humans. However, these berries were protected by thick toxic spines which could tear through normal clothing or robes and inject a painful neural poison which caused cramping and vomiting. The poison then induced a strength-sapping fever which fogged the mind and slowed the reflexes.

These spines, if carefully removed intact, were sturdy enough to be used as darts in a blowgun or flechette weapon. (Last Unicorn RPG module: The Way of Kolinahr: The Vulcans)