Lyhtrat is a great birch tree growing in lake Vuosaari. It was a sapling from Eitrat and planted to placate a growing unrest. The North Wind, who inhabits Eitrat, sent his eldest son to inhabit the sapling. Vuosaar vessels at the nearby university oversee the tree and have carved strengthening runes in its bark to speed up its growth. Every full moon, a blood sacrifice is smeared on the runes to further nurture the tree.
A recent source of debate at the university has been what to do in the event that Lyhtrat starts to bear fruit.