Answer: I don't think it is necessary to stake a new tree unless it is in a windy place, or it is already leaning and you want to train it to grow straighter. The controversy surrounds root development. Research shows that a tree that is allowed to move in a breeze will compensate for that movement by developing a stronger root system. One that is staked will tend to rely on the stake for support. I'd remove any stake that is attached to the tree and simply plant it on its own. But, if you decide to stake your new tree, here's how:
Drive 3 stakes into the ground just outside the rootball area, in a triangle pattern around the tree. Tie the trunk of the tree to each of the stakes so that it stands straight and tall. Check the ties every few months to make sure they're not digging into the bark of the tree trunk. You can safely leave the tree tied to the stakes for about a year, which will allow plenty of time for the roots to become established. Once your tree is firmly anchored in the ground you can remove the stakes and ties.
Japanese maples are heat and sunlight sensitive so be sure to find a spot that provide ssome afternoon shade for your new tree. You can plant now if you are very careful about watering (deep soakings once or twice a week, depending upon heat and natural rainfall).
Good luck with your new Japanese maple.
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