In the past 80 years, half of the UK's ancient woods have been cleared to make way for agriculture and conifer plantations.

What remains now takes up just 2% of the area once covered by forests dating back to at least 1600.

One of the fungi that flourish in the woods

By comparison, for all the deforestation during the past two decades, about 90% of the Amazon rainforest still stands.

In England, 198,000 hectares of ancient woodland remain - the equivalent of a 28 mile square forest - with 31,000 hectares in Wales, and 80,000 in Scotland.

Ancient woodland is made up of native broad-leaved trees such as oak and ash, home to a profusion of flowers, fungi, insects, birds and other animals.

Money talks

In the past 27 years, the trust has saved about 1,000 woods by buying up the land, in which members of the public are welcome to wander.

Under new chief executive Mike Townsend, the trust is switching its focus from woodland purchase to campaigning.

Mike Townsend wants forest protection orders

Despite the trust's annual income pushing the £15m mark, "we can't buy them all".

So the trust wants the Forestry Commission and planning authorities to recognise the importance of the woods, to get a protection designation to prevent more losses.

The first-ever official commitment to protect ancient woodland was made last December in the Government's "Forestry Strategy for England", which promised to look at ways to protect the forests.

In the meantime, the trust got on with the job of saving Penn Wood in Buckinghamshire, which had been earmarked for a golf course and 79-space car park.

Other woods still at risk include Upper Vert Wood in East Sussex, which is threatened by a plan for a rubbish dump, and Birkhill Plantation in Scotland, at risk from opencast coal mining.

"Woods like Penn Wood are just a remnant. This is fairly typical for the whole of Britain - this is not just a problem for Buckinghamshire," Mr Townsend said.