In Nausicaä of the Valley of the Wind, it's well established that the Tolmekians want to burn down the entire jungle. The villagers of the Valley of the Wind are opposed to this, especially Obaba, who explains:
Since the origin of the toxic jungle, a thousand years ago, people tried time and again to burn it. But time and again, their attempts did nothing but enrage the Ohm, and swarms of them spilled from the jungle and stampeded across the lands. They toppled cities, destroyed kingdoms, and killed thousands.
After toxic spores are found in the Valley's forest, the villagers demand to be able to go to the forest with fire-based tools and take action. Kurotowa seems to agree with them:
Soldier: If we give them tools to burn the spores, they could use them against us, instead.
Kurotowa: We have no choice. Hand over everything but their guns.
Initially the villagers only use fire to burn the spores directly, however, after the villagers find that they have infested entire trees, Obaba advocates burning down the forest:
This forest is doomed. We must burn it down. If we hesitate, the toxic jungle will engulf the entire valley.
The next scene shows the forest burning, seen by Gol from the mountain ridge.
Later, when Kushana returns to the Valley, we see that active battle has broken out between the villagers and the Tolmekians, with the villagers appearing to rush out of the burning forest and the Tolmekians rushing into the forest. The start of this battle is not shown on screen, but Kurotowa remarks:
All this over a little forest.
This implies the battle broke out because of a disagreement over the forest.
This was confusing to me, as I thought both the Tolmekians and the villagers were in agreement that the forest should be burned. Therefore why were they having a battle over the forest?
PS: Later, Gol, Gikuri and Niga make statements implying that they disagree with the decision to burn down the forest (though it should be noted that they were not actually in the Valley when the decision to burn down the forest was made):
Gikuri: You [the Tolmekians] plan to burn down the jungle, but we've learned to use fire only in small amounts.
Gol: That's right. Too much fire gives birth to nothing. Fire can reduce a forest to ashes in a day, while it takes the water and the wind a hundred years to grow one anew.
Gikuri: We prefer the ways of the water and the wind.
Niga: The princess will be devastated when she sees that our forest is gone.