Suprisingly height growth in a tree does not occur from the ground. If you made a mark on the trunk of a tree it would remain in the same place for the life of the tree. The branches extend from the buds and exisiting branches only expand in diameter, they do not lengthen. The trunk expands in diameter each growing season outwards. If we look at a cut down tree we can see the rings of growth each year. Spring is the lightest colour to autumn which is the darker colour wood. On a year with worse weather or other conditions there will be a small ring, with good conditions a large ring.
Just underneath the bark is a layer called the phloem which transports sugars throughout the tree. The sugars are made from the leaves during photosynthesis and are vital for new growth. Under this part is the cambium layer which grows each year, adding new xylem to the inside and new phloem to the outside.
When the wood is created “pipes” are built into it known as xylem. These are the vessels that carry the water and nutrients through the plant. The xylem are the dead cells in the trunk which are used just for this purpose.
From the centre of trunk are:
1. Heartwood (xylem)
Oldest dead cells, less active for transport. Darker wood.
2. Sapwood (xylem)
Dead cells, most active for transport.
3. Cambium
Growing part of trunk, produces xylem to the inside and phloem to the outside.
4. Phloem
Transports sugars throughout the tree.
5. Outer bark
Protective layer
interesting series adam. I especially liked the last two and can be used as a reference! For the future you may do something on all the different nutrients a tree needs and how each affects the tree or something like that.
Thanks for that. I’ll admit that I did do a bit of “information gathering” from the internet for some of it.