The mastic tree is a special tree that is found as a part of the In Pyre Need quest to help rescue the Phoenix. The "Harvest-twigs" option on this tree gives Mastic twigs, and left-click "Fletch" on the twigs turns it into Mastic weaving ribbon which is one of five weaving ribbons to be used on the pyre to kill the Phoenix and have it reborn in the Ritual of Rebirth.
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- A mastic tree is actually an evergreen but it doesn't have the same appearance as a usual evergreen.