Abscission

From Freepedia

Abscission (from ab- away from, and scission cutting or severing) is the shedding of a body part. It most commonly refers to the process by which a plant intentionally drops one or more of its parts, such as a leaf, fruit, flower or seed, though the term is also used to describe the shedding of a claw by an animal.

A plant will abscise a part either to discard a member that is no longer necessary, such as a leaf during autumn, or a flower following fertilisation; or for the purposes of reproduction.