A lenticel is a zone of the less dense cork, forming asperities coloured on the surface of the bark of the trees. One finds of it also sometimes on the surface of some Fruit S.

The lenticels allow the gaseous exchange between the atmosphere and internal fabrics of the plants. They are also used to absorb the gases, such C0₂.

It is often a key of identification to distinguish the species from trees. For example the Cherry tree and the Pommier resemble themselves much when they are in flowers. They are differenciables because the cherry tree has lenticels on its trunk but not the apple tree.