Biomechanics of Bark Patterning in Grasstree

  • Holly Jennifer Dale University of Calgary
  • Adam Runions University of Calgary
  • David Hobill University of Calgary
  • Przemyslaw Prusinkiewicz University of Calgary
Keywords: Bark pattern, fracture mechanics, primary and secondary growth, biomechanical model


Bark patterns are a visually important characteristic of trees, attributed to fractures caused by secondary growth of the trunk and branches.  A detailed understanding of bark patterns has been impeded by insufficient information regarding biomechanical properties of bark and the corresponding difficulties in faithfully modeling bark fractures using continuum mechanics.  Here we focus on grasstrees, which have an unusual bark-like structure composed of distinct leaf bases connected by sticky resin. Due to its discrete character, this structure is exceptionally well suited for computational studies. We created a dynamic grasstree model, which captures both the phyllotactic patterning of the leaf bases during primary growth and the emergence of fractures due to secondary growth.  The model reproduces key features of grasstree bark patterns, including inhomogeneities due to compression of leaf bases at the sites of inflorescences.

Author Biographies

Holly Jennifer Dale, University of Calgary
Department of Physics, Masters student
Adam Runions, University of Calgary
Department of Computer Science, PhD student
David Hobill, University of Calgary
Department of Physics, Professor
Przemyslaw Prusinkiewicz, University of Calgary
Department of Computer Science, Professor
1A Modelling plant structure