A project to plant six million trees across the UK as part of the Queen's 2012 Diamond Jubilee celebrations is being launched later in Hampshire.
The Princess Royal will plant the first tree for the Jubilee Woods Project, organised by the Woodland Trust.
As well as planting a tree, the princess will put a personal letter of support in a time capsule at Home Farm Wood, in Burkham, Bentworth.
Tree planting will take place from autumn 2011 until the close of 2012.
The trust has launched an appeal for landowners to plant a Diamond or Jubilee Wood on their own land.
Later this year a competition will be launched for the public to add their own personal story of life in 2012 to the time capsule.
Georgina McLeod, project head at the Woodland Trust, said: "We very much hope that people across the UK will want to join us in paying a very special tribute to the Queen, while at the same time creating something living and lasting to hand on to future generations.
"It's a great way to celebrate the Jubilee but also it's a chance to make your mark on Britain's future."
As part of the project there will be 60 special Diamond Woods - each of 60 acres - with hundreds of smaller Jubilee Woods also being created.