Sometimes, if you scar the trunk immediately above a leaf it will interrupt auxin (a growth regulator that suppresses back-budding) flow to the bud and activate growth. Pinching the growing tip (apical meristem), on the other hand, will result in most or all of the growing leaves producing branches. Where the plant is in its growth cycle and how much energy it has stored has considerable impact on how the plant reacts to either stimulus/treatment.

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