As Mateusz Herczka will create a virtual plant in « life support systems : Vanda » – 2005 ; the growth of this avocado tree is speculated randomly. This graphic representation is a human pattern of diffusion, inert propagation, and is in opposition with curves, living vegetal forces. With the dialectics forces/forms, vegetal/ar-tefact ; our habit to transfer everything into stationary state, controlled and programmed geometry is showed.