The rubber tree is grown
because rubber is made from the latex in its bark.
The rubber tree has roots made up of
a tap-root
and creeping roots.
In the bark of the rubber tree
there is a liquid called latex.
The latex is harvested
by making a slit in the bark,
that is, by cutting a piece of bark.
The latex makes the rubber that is used:
Rubber is in great demand all over the world;
more and more of it is needed.
But it is very difficult
to grow rubber trees well
and to harvest the latex.
They cannot be grown everywhere.
They need: