From Dust

Story related and cannot be missed. Wildfires is the sixth level of the story. This will unlock shortly after you guide your tribe to the exit.

This level is the first real time that your tribe will be in constant danger from fire. You will be able to move around the water trees (and once you build enough village, the fire trees as well) to help with this. At the beginning, you are left to your own devices. Fortunately, with a few clever alterations, you can easily complete this level.

You will encounter a pair of fire trees immediately after beginning the level. Direct your tribe to the first totem and then remove all of the earth around those trees by holding down . Once you’ve absorbed all that you can, dump it away from those trees. Fire from those trees needs vegetation to spread. Vegetation needs earth to grow. No earth, no fire. On either side of the first totem will be two solitary fire trees. Use the same method of removing the earth from underneath the trees.

Near the second and third totems will be three fire trees standing near on a hill with a river running behind them. Again, you want to remove the earth around them. This time though, removing the earth will isolate those three trees and they’ll be left on a little ridge by themselves. You can do the same for another group of three near the second totem.

The last group of fire trees is simple. Once you build a village around that totem, you’ll be able to move the fire trees wherever you want. Place them in water to easily take care of them.