With their roots deeply rooted in the ground and their branches soaring skyward, the trees seem unchanging. However, behind their bark, are hidden sentient beings who communicate, help each other, defend themselves.
Their discretion sometimes makes us forget that they deserve our attention when we could not live without them.
For this special day dedicated to forests on France Bleu, Johann Guerin receives Catherine lenne. She is a teacher and researcher in plant biology and author of the book In the skin of a tree at Belin. In Wait a minute !, it reveals the secrets of trees and pierces the mystery of their growth and reproduction.
Under the bark of a tree
The bark represents tree skin. Composed of flexible and waterproof cork, it is its very first line of defense in the face of attacks from the outside world. She ensures protection trunk, branches, but also large roots.
Deep bark, called “inner bark” is made of liberate. With a fibrous and tender appearance, it sometimes looks like the pages of a book seen on the edge, hence its name. “Liber” in Latin means “book”.
After the inner bark is found wood. It ensures the mechanical strength of the shaft, but not only that. The wood allows raw sap, a water loaded with mineral elements drawn from the soil, to circulate from the roots to the leaves. It also serves as a reserve for sugars which were made by the leaves during the beautiful season.