Glenfeshie - a 170 sq km sporting estate - contains a remnant of the great Caledonian pine forest that once covered much of Scotland. But no young trees have been able to grow up for many decades because the big red deer population, kept high for the sake of stalking by wealthy human hunters, eat the seedlings and saplings. The woods that remain are full of elderly trees.
Glenfeshie was designated as a National Nature Reserve more than 30 years ago. But that has not stopped its wildlife value gradually declining because of what conservationists see as mismanagement under a series of private owners.
Three years ago a mysterious charitable trust, Will Woodlands, bought the estate off a Midlands furniture manufacturer for about pounds 5m with the stated aim of improving nature conservation.
The trust, set up by a now deceased widow in memory of her wealthy husband, planned to keep the deer out of the remaining woods using large fences, and continue to maintain high numbers for stalking. But deer fences are a known killer of the rare capercaillie and black grouse, birds which fly into them. And, outside the fences, the woods would still have been unable to spread and regenerate.
The trust applied for tree regeneration grants from the Government's Forestry Authority but was turned down. Conservation groups like WWF believe they played a major part in persuading the Forestry Authority to refuse these grants on the grounds that Will Woodlands' plans did not give enough weight to regenerating forests and conserving natural species.
Now the trust has put Glenfeshie back on the market at pounds 5 to pounds 6m. It may yet end up in the hands of owners mainly interest in running it as a sporting estate - in which case the forest and wildlife would be at risk of further decline.