Oh, sorry, I was just reporting it really. Shortly after my comment I basically just brute-forced my way through tile by tile until I got to the south book, finished it, then got killed to exit the dungeon (getting extremely over-leveled in the process). Since I didn't have any reason to go down that far anymore, triggering the dryad wasn't a concern.
I tried to go back just now and I can't seem to reproduce it anymore (even though nothing I was trying to stop it worked before), so I can't test out this fix. If I find it happening on a different playthrough though I'll definitely see if it helps.
For the record, it was only triggering when I went South, not anywhere in the Depths, it was preceded by rustling, and there was definitely no way to avoid them even if I hugged the left/right edges and tried to go quickly.
Thanks for getting back to me, though! Really love the game, by the way! ♥