Travel to the heart of the Deadwoods and you can consort with Fudric Emberbark, who will be happy to burn your trees as a sacrifice and provide a random more valuable tree.
Upto 100 NFTs can be burned and upgraded at the same time to higher rarities. NFTs must be paired up with the same rarity to perform an upgrade.
Performing a mass upgrade will require running two transactions, the first transaction will cost 0.0025bnb to cover Chainlink VRF2, this can take a few minutes. Once VRF2 is ready, choose the NFTs to upgrade and run the second transaction.
There is a stats checker at the bottom to make sure you aren't burning any strong NFTs.
If you bring 2 common Money Trees to Fudric, he'll release an uncommon. Bring him 2 uncommon Money Trees and he'll release a rare one, and so on.
The upgrading ratios effectively makes Legendary NFTs worth 16 common NFTs, this is reflected in the dividends when staking these NFTs.
Fudric will burn these trees, not only literally, but also, from the Blockchain. So be sure to only select the ones you're happy to dispose of, some deeds are irreversible...