An estate owner plans to launch legal action against the body responsible for Scotland’s natural heritage unless a settlement can be reached in a long-running dispute over trees.

Luss Estates has accused Scottish Natural Heritage (SNH) of creating a “major eyesore in one of the Scotland’s foremost beauty spots” by “deliberately poisoning” 300-year-old beech trees.

It alleges  SNH has also subsequently refused to cover the costs of felling and removing the trees on Inchtavannach island on Loch Lomond.

Its lawyers have given the agency a deadline of the end of this week to reach a settlement, or they say they will seek damages through the courts.

The estate wants SNH to cover the costs of felling dead trees that are still standing, removing felled timber to the mainland, lost timber value and management and legal costs, totalling over £152,000.

They have also called for the body to make a public apology.

Luss Estates says it entered into an agreement with SNH in 2013 to remove rhododendron, beech saplings and also gradually fell mature beech trees, which SNH at that time considered ‘non-native’, over a five-year period.

It claims that instead the agency “decided to ring-bark and poison hundreds of beech trees all at the same time, without consulting the estate”.

Simon Miller, Luss Estates chief executive, said: “The local community was appalled when it saw what had been done to the ancient beech trees on the island, and the resulting blight on the landscape.

“It beggars belief that the body that is supposedly responsible for protecting our natural heritage left Inchtavannach looking like a wasteland.

“This is a tragedy that cannot be undone for generations.”

A spokeswoman for SNH said: “Inchtavannach is internationally important for its oak woodland but the condition of the woodland has been affected by a lack of regeneration, a lack of dead wood and the spread of non-native plants.

“We have worked with Luss Estates and the tenant over several years on agreed management measures to improve the condition of the woodland.

“We are disappointed to have received this claim as our staff continue to work closely with Luss Estates to find workable solutions to tackling the problems with non-native trees on Inchtavannach.

“We have asked our solicitors to respond to the letter, and it would be inappropriate for us to comment further at this time.”