DR JEREMY BURGESS / SCIENCE PHOTO LIBRARY DR JEREMY BURGESS / SCIENCE PHOTO LIBRARY
The bole of a sessile, or durmast, oak tree (Quercus petraea) showing the development of a large vegetative outgrowth or "burl". The tree is growing on a hillside in Cumbria, UK. The burl is about 2m from ground level and 70cm in diameter. The bark on its lower surface is unusually coarse and corky in texture. Burl wood is prized by woodturners, and for veneers, due to its complex and beautiful grain patterns. The cause of the reaction that produces a burl is usually unknown; possible sources include injury in the form of mechanical damage or attack by insects or fungi.
Model release not required. Property release not required.