"Khadgar's Whisker" is named after Archmage Khadgar. Prior to WotLK, alchemist/herbalist characters ended up with a surplus of this herb, and it commanded very low auction house prices on most servers. With the advent of Inscription, and the desirability of [Jadefire Ink], Khadgar's Whisker goes for a good price on most AHs.
Patch changes
Patch 6.0.2 (2014-10-14): Stacks to 200, up from 20.