Wood growth rings,coloured X-ray. Growth rings in wood are exposed by cutting across a tree trunk or large branch. Each ring represents a period of growth in which the tree formed new wood. Each year the outer part of the wood,the living part,lays down a new layer. The older layer dries out and dies,forming the hard mass of wood in the core,the heart wood. Each ring corresponds to a single year and allows the age of the plant to be calculated. A ring varies in width according to the climate that year | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Gustoimages |
Bildgröße: | 5956 px × 2950 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |