Apple Tree is a T-Spin Single opener created by Flyspeck101 with help from Nakamura's COpener Gang. It has a very high chance of going into 7-2 stacking in the fourth bag.
First Bag
The first bag requires O before S, and then either T or Z last in the queue. It has a cover rate of 20%, 30.48% including mirror.
Second Bag
The second bag is 100% with 180 spins.
Third Bag
This third bag will fail if you get Z before S before O and T before S:
If you get S before Z before L before O, you can either use hold to switch the order of L and O, or if T comes early you can place the S, clear the TSD and then complete the rest of the setup.
If you are unable to do the main third bag you can do one of these two compromise setups, depending on which of L and J comes first:
Note that the L before J setup is cleaner.
Fourth Bag
After the third bag, the player can go into 7-2 stacking/LST with a J tuck:
