The substantial rural holding now known as Marnong, and once called Green Grove, started off as a portion of a run called Bank Vale, which was held in the 1840s by William John Turner Clarke.
In the early 1840s the Scotch Company was no longer able to maintain the venture and the run was subsequently taken over in early to mid 1841 by Clarke who quickly installed John Edols, a young overseer, in the vacated manager's hut. This was Clarke's first undertaking in a district where he was within less than two decades to own the freehold title to more than 100,000 acres. In the immediate area, however, by July 1841 he had installed his brother Lewis on the small Plover Plains run, which lay to the west of Bank Vale on the other side of the Deep Creek. And by the late 1840s, Clarke had taken over the Hill Head run which adjoined Plover Plains on the north.
The run they set up, Bank Vale, lay some twenty miles north of Melbourne, to the east of the Deep Creek (or Saltwater River), and just beyond the site of the future village of Mickleham. The land comprised undulating open pastures and was well suited for sheep. From such descriptions it would appear that the present Marnong property is situated in what was the southwest part of this run.
The Bank Vale run itself was described as 'one of Clarke's most cherished stations and his only home in the Sunbury District. It was the address to which Hoddle wrote a letter in July 1850 informing Clarke that part of the Hill Head run had been leased to Captain James Pearson.