The Early Years

We begin with the tallest trees on earth, the towering redwoods, which can stand as high as 115 metres, taller than the Statue of Liberty. Even these mighty giants start life as a seed just a few millimetres long. For many trees, the creation of new life starts with one of the most dramatic displays in the natural world: blossom. To learn how seeds are actually made, we travel to a beautiful elderflower orchard blanketed by hundreds of thousands of tiny white flowers, to learn that blossom is crucial to a tree ‘having sex'. And once a seed is formed, it uses ingenious ways, like the spiraling sycamore helicopter seed, to travel far from the parent tree. And then from the bare soil a brand-new tree will begin to grow.

But the early years of young infant trees can be challenging. On the sunny Italian Amalfi coastline, we meet a lemon farmer whose young saplings must be looked after extra carefully. Their youthful ‘enthusiasm' to grow fruit when they're just a few years old can damage their delicate branches, so he builds scaffolding to support them. From Italy to Kew Gardens in London, where among its 11,000 trees, we learn how leaves are vital to helping trees grow tall and strong.

Coming in all shapes and sizes, leaves allow trees to make their own food using the sun's rays. But a tree needs more than just sunlight to grow. Water is vital for a tree to survive, and many trees have found ingenious ways to quench their thirst in some of the hottest places on the planet, from absorbing it from the air to sending their roots deep underground to find it. And in a eucalyptus plantation, we hear the incredible sounds a thirsty tree actually makes when it ‘drinks'. Eucalyptus trees are so thirsty they can drink about a bathtub's worth of water every day.

Some trees can reach maturity in a matter of years - the weeping willow grows eight feet taller in a single year, whereas the white bark pine can take 250 years, a quarter of a millennium, to reach their adult size! In the New Forest, historical tree graffiti on a 200-year-old beech tree reveals exactly how a tree grows; this tree, which was young at the time Britain was fighting sea battles against Napoleon Bonaparte, doesn't grow from the base of its trunk up, but from the top.

The seasons play an important role in any growing tree's life. At the end of this chapter in the trees' story we journey to the National Arboretum at Westonbirt, as its acer trees burst into a magical display of autumn colour to reveal exactly how this firework display of reds and golds, emerges, following a long summer of growth into adulthood, as trees are preparing for winter.