From the Woodland Trust site:-
Plant A Tree
From bare land to future forests
Amazingly in just 12 years, small saplings planted on bare land will develop into thriving native woodland complete with sturdy trees big enough for you to walk under, rich ground flora, and a host of wildlife. Today the UK is one of the least wooded countries in Europe and only 40% of these woods are native. Over the past 30 years the Woodland Trust has been working hard to create new native woodland throughout the UK for the benefit of both people and wildlife through the simple act of planting a tree.
Every Tree we plant costs us £15 to nurture that tree to maturity. Please donate today and plant a tree at one of our 4 beautiful sites around the UK, as a thank you we will confirm your tree planting with a certificate sent by email or post.
A big impact from a small act.