TREES, A LIVING RESOURCE
Wood is one of the most
abundant and versatile natural
material on earth.
Wood comes from trees.
Wood is made up of cellulose
Trees contain other substances
such as water, oils, resins,
What is sap?It’s a solution of water and
nutrients that circulates in the tree from
roots to trunk, branches and leaves.
WOODS GIVE US...
1. BARK (corteza): it is the most external layer of the tree and protects tree
from damage (extreme temperatures, bad weather, insects).
2. CAMBIUM (líber): it takes the sap from the roots to the various parts of the
3. SAPWOOD (albura): the youngest part of a trunk, which has a clear colour.
4. HEARTWOOD (duramen): it is the part of a trunk that gives harder and
more consistent wood. It is the wood used for making things.
PARTS OF A TRUNK
How old is a tree?
It’s possible to know how old
a tree is thanks to the
annual rings are seen when
a trunk is cut.
The clear rings represent
the tree´s growth in spring
and the dark ones are
related to autumn, when its
growth is lower.
THE PROCESS TO GET
FELL (TALAR): It is carried out in
winter. Bark and branches are all removed
from the tree and they are used for gardens
or like a combustible.
(TRANSPORTE): To carry timber to
sawmill by lorry, train or fluvial/maritime
CUTTING UP (CORTE): Timber is cut in
different pieces and sizes in the sawmill.
THE PROCESS TO GET
DRYING (SECADO): It consists of removing natural
moisture from timber. This can be done in two
Natural (slower and cheaper) and with kilns or
air-dried (quicker but more expensive)
How does it feel?: Color, texture, brightness…
Hardness: Can tools, nails, screws...make holes in it?
Does it wear or scratch by other objects?
Density: It depends on mass and volume. Let us know if it
is a heavy or light wood.
Moisture content (grado de humedad): Different woods
have different mass of water and their properties and
durability depend on it.
Thermal and electric conductivity: Woods are not a
good conductor of heat and electricity.
Strength: The ability to resist forces without breaking and
bending depends on the type of wood. It´s very good when
forces act along the grain (fibra).
TYPES OF WOOD
Deciduous (hoja caduca)
trees which drop their leaves
in winter and are the typical
round top tree shape.
Coniferous (coníferas), which are
cone bearing evergreen (hoja
perenne) trees which generally
have the typical Christmas tree
Softwoods are cheaper than hardwoods and easier to work.
Hardwoods are attractive woods but they are not easy to work.
MAN MADE WOODS
Man-made wood has been made up of bits of
wood which originally came from a tree.
TABLEROS DE FIBRA
WORKING WITH WOOD
To make a wood object we must follow the next steps :
MARK AND DRAW
Natural woods can be sold with different shapes: