Michael Bruce, the owner of the 10,000-hectare Glen Tanar estate on Deeside, is to be visited by officials from Scottish Natural Heritage (SNH) tomorrow after complaints that forestry operations damaged trees, killed plants and scarred the landscape.
The alleged damage was discovered by a mountaineer, Derek Pyper, from Aberdeen, during a cycle ride up Glen Tanar. He was shocked to see that wide tracks had been bulldozed into the woods.
"There was a large area of what had been attractive woodland reduced to deep mud – not a pretty sight," he said.
Glen Tanar contains some of Scotland's finest native woodlands, which are meant to be protected by law. The glen is covered by five conservation designations, and lies in the Cairngorms National Park.
Conservation biologist Dr Adam Watson has seen pictures of the damage and says heavy machinery has killed vegetation and left native trees vulnerable to rot by skinning their barks.
He described the damage as "scandalous".
"It's the worst I have seen in many woods over recent years, and particularly reprehensible because it is in a beautiful section of ancient pine wood. I regard it as land vandalism on a large scale."
Watson complained to SNH and demanded that action be taken to curb alleged "unlawful" activities in Glen Tanar.
SNH's Tayside and Grampian area manager, David Bale, said: "We've received a complaint about potential damage at Glen Tanar and will visit the site on Monday to investigate." The Forestry Commission is also understood to be looking into the matter.
Landowner Michael Bruce accepted that the forest was in "poor condition", but argued that "one of the wettest summers in decades" was partially to blame.
He said: "Glen Tanar Estate operates at all times within our agreed long-term forest plan, which was prepared after public consultation and consultation with SNH and the Forestry Commission."