Through the Mists, the new World Quest series added to Genshin Impact with Version 2.2, largely takes place on Tsurumi Island.
You'll need to complete the chain to dispel the fog that permeats Tsurumi Island, preventing you from exploring fully.
The third quest in the chain is The Sea of Fog and the Rite of the Trees. To begin the quest, you miust wait a day after completing the second quest of the chain (i.e. after the daily reset), and then go and speak to Kama.
Here's our guide to completing it.
Kama will direct you to Ruu on Tsurumi Island.
Following the cutscene, you decide to try and destroy the tree to prevent the ritual, as well save Ruu from being sacrificed.
At half health, a cutscene will play in which electric orbs leave the area. Track them down using the markers on the minimap, and destroy them.
Be mindful that Electro and Physical attacks will be ineffective, and be aware of other enemies spawning.
Return to the perch nearby and destroy it.
Now you've destroyed the first tree, there are three left. To help you out, we've taken screenshots of each tree and their orbs.
The same deal applies -- watch out for enemies spawning.
While all the orbs aren't visible in these images, you'll easily find them using your minimap markers.
Once done with the three trees, return to the ceremonial site. A cutscene will play and you'll be returned to the starting point om the island.
Speak to Ruu, who's rather annoyed at you, then return to Sumida in Inazuma City.
This concludes The Sea of Fog and the Rite of the Trees, and the third of four quests to clear the fog.