Wood anatomy (8) live and dead knots

Throughout history, we have used wood in our everyday life to make fire, create tools, build shelters and more recently to make paper and engineered wood products. Wood allows for modern ways of construction using sustainable resources and its ability to store carbon contributes to our fight against global warming. As ordinary as it may seem, wood is actually an extremely complex composite material with unique features. In order to utilize the full potential of wood, it is essential that we understand its hierarchical, anatomical and chemical structure, the material behavior that results from its complex built-up and the environmental impact of wood products. This is why we created these short series that highlight the various aspects of wood.

The lecturer in this series is Prof. Dr. Callum Hill. He has been a senior lecturer in wood science at Bangor University and a Professor of Materials Science at the Centre for Timber Engineering, Edinburgh. He is now a Senior Visiting Research Fellow at the University of Bath and a Visiting Researcher at the Norwegian Institute of Bioeconomy Research and has his own consultancy that deals with life cycle assessment, carbon footprinting and sustainability assessments.

The videos were produced at Aalto University in Finland under the direction of Prof. Dr. Lauri Rautkari, who is leading the Wood Material Science and Technology research group (https://www.aalto.fi/en/department-of.... The videos are part of an open access Wood Science course (https://openlearning.aalto.fi/course/...) at the Aalto OpenLearning platform, designed by Lauri Rautkari, Michael Altgen and Daniela Altgen.

The videos were shot and edited by filmmaker Tone Anderson.

Keywords:
Hardwood, softwood, heartwood, sapwood, juvenile wood, pith, growth rings, latewood, earlywood, radial, tangential, longitudinal, cambium, tracheid, vessels, fibers, ray cells, parenchyma cell, epithelial cells, resin channel, bordered pits, phloem, xylem, cell wall layers, secondary cell wall, middle lamella