Tree rings are records of the influence of environmental conditions, their anatomical characteristics record growth rate changes produced by these changing conditions.
The microscopic structure of conifer wood consists of two types of cells: parenchyma, which have an oval or polyhedral shape with approximately identical dimensions in three directions, and strongly elongated tracheids.
Tracheids make up more than 90% of timber volume.
The tracheids of earlywood formed at the beginning of a growing season have large radial sizes and smaller, thinner cell walls.
Then, the first tracheids of the transition zone are formed, where the radial size of cells and thickness of their cell walls changes considerably.
Finally, the latewood tracheids are formed, with small radial sizes and greater cell wall thickness.
This is the basic pattern of the internal cel structure of conifer tree rings.
Tree rings are records of the influence of environmental conditions, their anatomical characteristics record growth rate changes produced by these changing conditions. The microscopic structure of conifer wood consists of two types of cells: parenchyma, which have an oval or polyhedral shape with approximately identical dimensions in three directions, and strongly elongated tracheids. Tracheids make up more than 90% of timber volume. The tracheids of earlywood formed at the beginning of a growing season have large radial sizes and smaller, thinner cell walls. Then, the first tracheids of the transition zone are formed, where the radial size of cells and thickness of their cell walls changes considerably. Finally, the latewood tracheids are formed, with small radial sizes and greater cell wall thickness. This is the basic pattern of the internal cel structure of conifer tree rings.
Pinophyta