Leaf stipules, aka bud scales, are appendages that usually protect buds as they form. In the Ficus genus, stipules are modified in a cap shape that serves to protect the entire shoot tip. Abscission (shedding) of the stipules is a normal part of your tree's morphology, and occurs when the first leaf of a new branch begins to
form a petiole (leaf stem) and it pulls away from the terminal bud. If you want the tree to grow taller, do nothing other than keep it healthy.

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