The structure of a tree is simple and curious: some ramifications in the air to catch the light, some branching underground to pick up the food. But branches and roots are similar: both are developed linearly, until at a certain point, following an algorithm written in the genetic code of the plant, they split, bifurcate, or are tripled, growing in space with a progress which will be sensitive to obstacles of soil or climatic conditions of the place. The drawing of the bare branches and of the roots, flattened by the simplicity of a pattern in pencil, creates an embroidery, an imaginary warping which can be generated countless times, always different.