EDITED:
This would be a tool that works like Sunder Magic but access to it is based on Herbalism ranks not whatever Sunder Magic is based on. It would reduce Herbalism's reliance on plants, which are prone to unblockable thievery or destruction. As Aethereal mentioned some of them are key reagents needed for certain types of recipe.
Sunder Magic is used for herbalism and Alchemy
You can use litrally anything in Herbalism and Alchemy. All those items you find that you think are proberbly useless... You can use them :)
Herbs which are not key reagents can be sundered too.
Sorry, allow me to rephrase this. I am suggesting a tool that has the effect of Sunder Magic but works off of Herbalism ranks, not Alchemy ones.
CakePlease: Yup, I know. But to concentrate research on a certain element, Sunder Magic is useful.