Imagine a plain made of tall grass that sways in a gentle breeze. Everything is a deep green and there is a riot of life sprouting from the black ground. A few days later, the grasses turn brown and the animals burrow deep underground. Another day later and an inferno sweeps through the area, completely burning all of the grass and leaving only ash in its wake. The grasslands regrow from their roots or the seeds they dropped and have adapted well to the season cycle, but how would the trees survive?
This biome would look like a savannah, so the trees aren't very dense, but they are bordered by grass. The grass grows very dense and burns hot. The fires sweep through about every month, and an area of grass probably burns for around 5 minutes. On earth, natural fires can reach 800 C, which is probably the ballpark of what these fires would be at.
I know redwoods store water in their bark, but there isn't as much water in the savannah as there is in redwood forests, so I don't think that would be a complete solution.
So the question I have is what is the main adaptation that trees(or tree-analogs) would need to survive and thrive in this climate? Thee trees are carbon-based, and the solution also has to work for saplings of the tree otherwise, the species would just die out.
There are a few questions about fire and plants, but none that cover this exactly. This question deals with what a plant would need to not catch on fire: Fireproof Plants
This question deals with a flash fire(conclusion, no effect): Fire Resistant Flora