Oblivion had a unique kind of plant placed across Cyrodill, the Nirnroot.
As opposed to other plants that you could find in the game, this one did not regrow after time, and there was also a quest attached to it, which had you collect all 100 Nirnroots that were hidden in the lands.
From a gameplay perspective it was a nice distraction from the usual questing – Oblivion (and as far as I know other ES games as well) didn't have that many "collectible" quests.
So, will there be Nirnroots in Skyrim?
Best Answer
Yes, there will be Nirnroots in Skyrim:
This image is from the G4TV Skyrim demo. You can also see Nirnroot in the Skyrim Trailer.
You can find information about its alchemical properties, location, quests and lore on the Elder Scrolls Wiki Nirnroot page.