Jumbuck Pastoral is having the biggest shake-up in its 135-year history as part of the MacLachlan family's succession planning.
Brothers Jock and Callum MacLachlan have spent most of their working lives with Jumbuck - 30 years for Jock and 25 years for Callum - and are stepping down as co-managing directors.
"With a rationalisation of Jumbuck as a result of a family succession, we have both given notice and will finish up at Jumbuck at the end of September," Jock MacLachlan said in a newsletter released last month on the company's website.
"We have spent the past 14 years as joint managing directors and feel this has been a good era at Jumbuck, with some weather events thrown in that were a bit difficult for us all.
"But, of the things that we could manage, we felt we have given it our best crack."
The family empire covers 5.2 million hectares across a portfolio of 12 stations worth hundreds of millions of dollars in WA, South Australia, the Northern Territory and New South Wales.
The move to split it between the two brothers and their father Hugh MacLachlan comes hot on the heels of the family selling the famous Rawlinna station in WA to mining magnate Andrew Forrest, announced in April this year.
Rawlinna, 400 kilometres east of Kalgoorlie, is Australia's biggest sheep station and wool producer, spanning just over one million hectares.
Unconfirmed media reports at the time of that sale said Mr Forrest's Fortescue Metals Group was considering using Rawlinna for renewable energy projects.
But the official line from Fortescue was that it was intending to continue pastoral activities.
The MacLachlan family at the time declined to comment on why they had sold Rawlinna and what it might be used for in the future.
Mr Forrest already owns substantial cattle country in this region of WA.
Last year he bought the well-known, 634,000ha Balfour Downs station in the Pilbara for more than $32m, from TBG Agri Holdings.
Mr MacLachlan said he and his brother were not moving out of the pastoral industry.
He will continue directing Meda station (505,857ha), just out of Derby, and McCoy's Well (running 13,700 Poll Merino sheep), in South Australia.
Callum will continue with Killarney and Wave Hill stations, in the Northern Territory, and Springfield, in NSW.
Mr MacLachlan said over the years there had been highs and lows.
"Many of the highs have come from working with the Jumbuck team, which includes all our people across all the stations and the office staff," he said.
"While neither of us have envisaged this as scripted when we commenced working for this business, change is unavoidable and with it, we flex, re-focus and move on.
"One chapter closes and another one opens.
"We wish owner and chairman Hugh MacLachlan and our sisters, Airlie MacLachlan, Islay McKenzie and Brooke Yates, good seasons, markets and fortune with the future management of Jumbuck."
Hugh MacLachlan said in the newsletter it was regrettable to see Jock and Callum depart the Jumbuck family as part of planning for family succession.
"As joint managing directors, they have served Jumbuck for a very long period of time with distinction," Mr MacLachlan said.
"It is their enterprise and financial expertise - and theirs alone - that expanded Jumbuck's interests into the Victoria River district of the Northern Territory.
"In the meantime, Jumbuck will carry on as before with my daughters Airlie, Islay and Brooke as directors taking more active roles where they can."
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