caducous

adjective

1. Botany. dropping off very early, as leaves.
2. Zoology. subject to shedding.
3. transitory; perishable.

adjective

1. biology (of parts of a plant or animal) shed during the life of the organism

1. Detaching or dropping off at an early stage of development. The gills of most amphibians and the sepals or stipules of certain plants are caducous.