James Bruce died aged 85 following a lengthy illness in April this year.
A staunch supporter of forestry development all his life, he was awarded the CBE in 1992, having dedicated more than four decades to the industry including the founding of Scottish Woodlands.
His published will has revealed he had built up a £3,787,873 fortune by the time of his death.
He ordered that the vast majority be passed to his third wife Mary and his seven children though he did gift £5000 to Scottish Opera.
His fortune was made up of his £650,000 country estate, Dron House, in Perth, and his household belongings valued at £612,000. He had a £2750 gun collection and a private wine cellar worth £16,000. The remainder of his estate was made up of a large stocks and shares portfolio.
Mr Bruce was born in August 1927 to Edward Bruce, the Earl of Elgin of Broomhall Dunfermline and Katherine Bruce.
He was educated at Scaitcliffe, Surrey and at Eton College before conscription in 1945 saw him sent to RMA Sandhurst for training.
Following in the footsteps of brother Andrew, he joined the Scots Guards, but he missed the war.
After completing National Service he undertook training at the Royal Agricultural College in Cirencester.
In 1967 Bruce launched a business plan to provide professional forest management services to forest owners.
The concept took off and grew into a significant industry before he eventually retired in 1993.
He is survived by his seven children, 14 grand-children, his wife Mary Elizabeth and her family of two children and four grand-children.