The Musical forest

Lorenzo Pellegrini shook his head and walked away, knee deep in snow. He wasn't going to waste his time on that tree. Too many branches. Branches mean knots in the wood. And knots in the wood spoil its resonance. Pellegrini is a tree picker. He will find you the spruce in ten thousand that is just right. He will find you the Stradivarius tree.

"Lentement, lentement, lentement," he says. "Slowly, slowly, slowly". That's how violin trees should grow. "Up in these mountains, they grow so slowly sometimes they stop growing altogether. They just gather strength. There are trees up here that are a thousand years old!" His blue eyes are wide with wonderment. "Can you believe that?!"

Pellegrini's been working the forest since he was nine. Growing up in Italy's Abruzzo mountains, he and his family would go deep into the woods each year, hours and hours from the nearest village, build a cabin to live in and stay there for eight months, cutting down trees, chopping up logs. "I used to give my leftover polenta to the wolves," he says.

The forest that sings

When he was thirty he discovered the Risoud Forest in Switzerland's Jura Mountains and never wanted to leave. This is where Antonio Stradivari sourced some of his wood to make the best violins ever made. Thanks to Pellegrini and a few like him, this forest still provides some of the world's best "tonewood" today.

Now eighty-three, Pelligrini still climbs trees like a squirrel. And tends the forest as if it were his garden. Weeding out the beech trees that would smother his precious spruces. "For the trees to grow slowly and regularly, you have to let them grow close together like the hair on your head," he says. "And there shouldn't be too much water. The tree's heart should stay dry. That gives the best wood. Solid. Enormous resonance."

Gardening for the 24th Century

Pellegrini "gardens" the forest, as he puts it. But he gardens for people who won't be born for hundreds of years. So that there'll be fine resonance spruce in the 24th Century.

Once he has found the perfect tree, he has to wait for the perfect day to cut it down. That day comes at the end of autumn when the sap has sunk back into the ground; and when the moon is lowest on the horizon, when it's furthest from the Earth. Because, apparently, the moon's magnetic field doesn't only tug the waters of the sea and make the tides, it tugs up the sap. On that day, the tree is as dry as it can be. A ceremony is organized with the other foresters. It's usually the youngest who has the honor of felling it.

All of history in this wood

Driving down to Le Brassus, a little mountain town near the forest that houses many of Switzerland's most prestigious watchmakers, Jean-Michel Capt points to a mountain shrouded in cloud. "They say that when you can see that peak, it's going to rain," he says. "And when you can't, it's raining already."

Capt is a craftsman and an inventor. He uses the resonance wood Pellegrini finds to make guitars. In his workshop he shows me a strip of tonewood from a tree at least 350-years old. Its grain, its lines, are dead straight and close together. Put your finger on one line - that's the British army going over the top at Ypres. On another, that's Louis the XIV building Versailles. This one takes you right back to the Pilgrim Fathers.

The wood transforms sound

To demonstrate the wood's acoustic qualities, he takes out a little musical box. Winds it up and it tinkles. He places the tinkling box on that strip of wood and the tune suddenly fills the room. Not only much, much louder but warm and full.

Later we walk through the village, past schoolchildren whose teacher is taking them off sledging. We're going to meet one of the many musicians of the Rissoud Forest. By the side of a wood-burning fire, by a table he made from a giant spruce, David Guignard takes out his cello and plays a bit of Bach. Round here you wouldn't be surprised to learn that people wear paper shirts and grate wood shavings on their spaghetti.

"My father was a forest warden and my grandfather built a cabin for us in the woods," he recollects. "So the best moments of my childhood were in the forest. I was happy to live at the foot of those trees." Guignard's music teacher taught him that wood is never quite dead. It is always reacting to changes in temperature and humidity, always evolving. I listen to the crackle of the fire and the sound of cello strings making the wood sing. And think that I'll never quite hear this music in the same way again. Because around here, when you hear an instrument like this, you think of the snow and the wind and the cuckoos and the bees in those tall violin trees.