Which tree weighs as much as 450 elephants and is the heaviest living thing on Earth? How can a tree have bark on its trunk that grows in rainbow colors? What is the strange red liquid that pours from the trunk of the dragon’s blood tree? And where in the world can you see a 1,000-year-old tree that has two churches carved into its trunk?

Meet some extreme trees -- Giants of the rain forest -- Rainbow gum trees -- Extreme spiky trees -- The dragon's blood tree -- A poisonous tree -- Amazing banyan trees -- A prehistoric tree -- The chapel oak -- Science lab -- Science words.