A series of twenty non-fiction science readers which engages children in the world around them. Why are flowers different colours? How do we know how old a tree is? How can plants grow in deserts? You can find the answers to these and other questions about plants in Why Do Leaves Change Colour? Why are flowers different colours? How do we know how old a tree is? How can plants grow in deserts? You can find the answers to these and other questions about plants in Why Do Leaves Change Colour?