Forest Tree seeds are granted to Koroks following a successful Korok Ceremony in the hopes of spreading Trees across the Great Sea. The Great Deku Tree intends for the new Trees to absorb the water that comprises the Great Sea and eventually reduce it, allowing the residents of the Great Sea to traverse by land to other parts of land that were formerly islands. Forest Trees are also said to be the source of the Great Deku Tree's power, and thus the source of life for the Koroks as well.
When Link first encounters the Great Deku Tree in search of Farore's Pearl, the young hero learns that he cannot be given the Goddess Pearl until the Korok Ceremony is complete. However, the Ceremony cannot be initiated as Makar has gone missing, requiring Link to enter the Forbidden Woods and retrieve him. After Makar is rescued from Kalle Demos, the Koroks perform the Ceremony, preparing the Great Deku Tree to release the seeds for the Forest Trees before sending the Koroks out into the Great Sea to search for islands to plant them.
Later, Link encounters the Koroks that flew across the Great Sea and finds that the seeds have grown into saplings. However, the saplings have begun to wither inexplicably, leading the Koroks to suspect that the other saplings have wilted as well as part of Ganondorf's malignant designs, causing their respective saplings to wither. To rectify this, the Koroks request that Link brings the Forest Water that surrounds the Great Deku Tree and sprinkle it onto the withering saplings in the hopes that they will flourish. In order for them to all become healthy once more, Link must sprinkle the Forest Water on them all within 20 minutes (30 minutes in The Wind Waker HD), allowing them to collectively grow into large trees.
Once Link has rescued all of the Forest Trees, a Piece of Heart will spring forth from the nearest Forest Tree. Afterwards, the Koroks and the Great Deku Tree will express their gratitude to the young hero, and invite him to return later to see the forests grown from the Forest Trees' roots.
|Mother and Child Isles||Rown|
|Eastern Fairy Island||Olivio|
|Needle Rock Isle||Elma|
|Cliff Plateau Isles||Aldo|
- Much like the Great Deku Tree, the Forest Trees all have faces. Forest Tree saplings bear melancholy faces while healthy Forest Trees have more pronounced, happy faces.
- "Every year after the Koroks perform this ceremony, they fly off to the distant islands on the sea and plant my seeds in the hopes that new forests will grow." — Great Deku Tree (The Wind Waker)
- "Forests hold great power: they can change one tiny island into a much larger island. Soon, a day will come when all the islands are one, connected by earth and grove. And the people who live on that great island will be able to join hands and, together, create a better world. Such is my dream." — Great Deku Tree (The Wind Waker)
- "If we are unable to hold our ceremony, we will not be able to raise any new forests. If that comes to pass, then evil days will follow. The Great Deku Tree's power will wane, and our power will wane with it... We might even wither altogether..." — Korok (The Wind Waker)
- "As it happens, you have come just in time for a ceremony that the Koroks hold but once every year. It is about to begin. I shall grant the pearl to you once their ceremony is complete." — Great Deku Tree (The Wind Waker)
- "N-No! It is not that, O Great Deku Tree! Makar...fell into the Forbidden Woods! I told him to be careful! But still Makar flew above the Forbidden Woods, and as he drew close to it..." — Linder (The Wind Waker)
- "Hello, swordsman. I haven't seen you in a while. How have you been? I've come here to plant the Great Deku Tree's seed... But look! Usually, the forest trees sprout quite vigorously wherever you plant them, but for some reason, this one has withered... ...I'd be willing to bet that the trees my fellow Koroks have planted are withering, as well." — Rown (The Wind Waker)
- "It seems that when one tree fails to grow from its seed, all forest trees from that year's seeds wither and fail to grow tall and mighty." — Rown (The Wind Waker)
- "Huh? You say the forest trees my fellow Koroks have planted are withering? So, it's true! As you can see, the forest tree I have planted is doing the same. I can't help but think that this, too, is tne result of Ganondorf's evil plot. Could it be? ...Regardless, in order to bring the life back into this poor withered sapling, I will certainly need Forest Water." — Rown (The Wind Waker)
- "What are we to do? If we are not able to nurse these trees to health, the forest will never spread and the Great Deku Tree will slowly wither and die... ... Maybe if we could sprinkle the water from the Forest Haven on the tree... Maybe then this sapling would be saved. That water is the wellspring of the Great Deku Tree's life force. Swordsman! Could you go to the Forest Haven and get some of the water that flows around the Great Deku Tree? Could you get some and sprinkle it on this poor forest tree? Please? Please help me!" — Rown (The Wind Waker)
- "Thank you very much, swordsman. You must find [X] more of my fellow Koroks. If you pour that Forest Water on all of our trees, then the trees will surely grow strong again. But remember: in just XX:XX, the Forest Water you have will turn into plain water. So hurry up and look for my fellow Koroks!" — Rown (The Wind Waker)
- "Swordsman! Come see how healthy my forest tree has become! Wow! I'm so happy! Thank you so much!" — Rown (The Wind Waker)
- "Word has reached me that you performed admirably! Thanks to the miraculous effects of the Forest Water, I can smell the trees growing across vast distances. Please accept the Koroks' and my sincerest gratitude. We are eternally in your debt." — Great Deku Tree (The Wind Waker)
- "You should return once this tree has spread its roots to create a large forest. I'm certain it will be quite beautiful." — Rown (The Wind Waker)