Our camp fire in the woods was running out of logs to burn. So we had to chop fallen branches into smaller logs. After doing this, I looked at the freshly revealed inside of the wood and discovered that it had an interesting story to tell…
What do the rings mean?
Why are there funny marks?
In the Spring, trees grow, forming new cells with thin walls. You can see this as the light-coloured rings in the cross-section of a tree. Then as Summer comes to an end, growth slows down, forming smaller cells but with thicker walls. You can see this as the dark-coloured rings in the cross-section of a tree. Therefore, to find out how old a tree is, you can count the number of light rings OR dark rings, as over one year, the tree will develop both a light and a dark ring. The tree doesn’t grow at the same rate in Autumn and Winter because, if they are deciduous, trees lose their leaves so they cannot photosynthesise, and the rate of growth is very slow. This process of growing cells and forming rings explains why the diameter of a tree increases, it gets thicker, as it grows over the years.
It turns out, the life of a tree can be hard! Looking at the sizes and position of the rings as well as any scars can reveal information about the sunlight, wind and even if there was drought, fire, diseases, injuries, pollution and insect issues. The effects become part of the physical history and story of the tree. This can be useful to help us understand more about what has happened in the environment in the past.
Forest Academy. (No Date) Annual Growth Rings
Fritts, H. (2012) Tree Rings and Climate