Lets put this very simply.

A druid or sentinel attacks you useing their grove. So you exterminate all the plants there. This has acheived nothing. A grove is just as powerful with or without the plants. The plants within the grove do not control the amount of power that the grove has. All the skills in groves use energy that is provided by the sun. All you have really acheived in this action will be to get yourself enemied by Oakstone and caused there to be less herbs to sell you you and the rest of achaea thus raiseing the prices. And caused an annoyance to the denzins of the forest.

Mandrake, Lord of Nature

Penned by my hand on the 8th of Scarlatan, in the year 243 AF.