Locals are likely to encounter competition from outside interests when the acclaimed Eastern Riverina mixed farming property Karbarook goes up for on-line auction next month.

Karbarook is a 954 hectare (2358 acre) property located in southern NSW mixed farming heartland at Milbrulong, roughly midway between Lockhart and The Rock.

It is owned by Richard and Sally Simpson, who are selling with the intention of buying other country closer to their home property further west, Boongara at Jerilderie.

They have listed Karbarook for sale with Elders Wagga Wagga and it will be offered on-line by AuctionsPlus on March 5.

Bids for Karbarook are expected to be lodged in a range around $8.5 million.

Situated in the old locality of French Park, 25 kilometres west of The Rock and 50km south-west of Wagga Wagga, Karbarook has a long history of ownership by the extended A'Beckett/Simpson family.

Originally part of Tootool Station (earlier spelt Tootal, when held by the Ashcroft family at the turn of last century), it was acquired as Tootool West in the early 1930s by Thomas A'Beckett, the agriculture-focused scion of a prominent Melbourne legal dynasty.

It was he who changed the property's name to Karbarook, after the A'Becketts' family seat at Armadale (VIC).

The new name was soon in the rural press headlines in connection with the owner's successes in local and regional field wheat competitions.

Today Karbarook is managed for the Simpsons on a contracting basis by adjoining landholders, the Sly family, principally as a dryland cropping operation.

They also run a complementary Merino sheep enterprise beside the main operation.

Described as nearly 80 per cent arable, the property is mostly level with red to grey clay loam soils.

There is also an area of hill country where between 500 and 600 ewes are typically run on natural pastures.

The seasonal Bullenbung Creek runs through the eastern end of the property, providing useful shelter with its associated riparian timber.

Cropping paddocks have a long history of soil-enhancing crop rotations, direct drilling and fertiliser use, including lime and gypsum applications as required.

The mainstay cereal and oilseed crops are rotated with legume crops to build soil fertility.

The bumper 2020 harvest across 705ha of cultivation saw wheat yielding 6.5t/ha, barley 7t/ha and canola 2t/ha.

A similar area is being readied for 2021 sowing.

This area is comprising 195ha of wheat, 158ha of canola, 100ha of field peas and 252ha of vetch.

Average rainfall is 430mm and apart from the seasonal creek, the property is watered by dams in all but the hill paddock, which is serviced by a trough system.

Most of the dams have recently been de-silted.

The double-brick homestead of four bedrooms is set in low-maintenance gardens with a tennis court and features views to The Rock.

Built in the early 1900s, and retaining period features, it was home to three generations of the A'Beckett/Simpson family until their base shifted to Jerilderie, and more recently it has had rental tenants.

Working infrastructure includes five machinery sheds of steel or timber construction, a workshop, steel sheep and cattle yards and seven silos of 400t combined capacity.

The property is subdivided into 15 main paddocks incorporating a laneway system and planted tree lines.

By PETER AUSTIN