Last I knew, infernoing a forest grove will destroy the herblife, but
fires will still burn there. If you really want to put in fire breaks,
you need to have it exterminated by a necromancer...that destroys the
room as forest completely. But is that what Haern stands for? I hope I
misunderstand.

Kestryl

Penned by my hand on the 21st of Slyphian, in the year 57 MA.