“tree parts”:
1-roots
Roots are the underground part of a tree. The primary root or taproots grow horizontally downwards, with lateral roots arising from the taproot. Each root is surrounded by many, tiny root hairs that increase their area of absorption.
2-crown
They are the topmost portion of a tree that may vary widely based on their shapes and sizes. The crown is made up of the following parts:
a- leaves: Usually the green part of a plant that remains attached to the crown. Leaves are also known as the factories of a tree. A collection of green leaves is called foliage.
b- Branches: The first thick branches of a tree arising from the central wooden axis are called boughs while the smallest terminal branches of a tree are known as twigs.
c- flowers: The most colorful and attractive part of the plant that remains attached to the terminal branches. It later develops into a fruit.
d- Fruit: The edible part of the plant that develops from the flowers. It contains the seed that gives rise to a new plant.
3- trunk or bole
The trunk is the central wooden axis of the crown that is typically brownish. They contain a network of small tubes that runs between the roots and the leaves, thus acting as the plumbing system in the plant. A typical tree trunk shows six parts:
a- Outer bark: The outermost layer of the trunk, branches, and twigs of the tree. The bark of some plants has a characteristic odor and scent.
b- Cambium: The thin layer of living tissues consisting of growing cells that are present just inside the bark. Every season they add a new layer to its trunk, thus producing a visible annual growth ring in most trees.
c- Sapwood or xylem: The youngest layers of wood that are made up of a network of living cells. Over the years, the inner layers of sapwood die.
d- Heartwood: The older and dead xylem cells found close to the center of the trunk and thus are usually darker than xylem. They are filled with stored sugar, oils, and dyes.
e- Pith: The tiny dark spot present at the center of the tree trunk that is highly protected from damage by wind, insects, and animals.
f- Inner bark or phloem: The pipeline located between the outer bark and the cambium of the tree trunk.
