I believe the _farmstead_ here refers to the buildings on the farm, while the _paddock_ refers to the fenced-in land associated with the farm. The definition in the OED is.
> A plot of farmland and the buildings upon it; a homestead; a farmhouse and its adjacent outbuildings.
The third of these possibilities seems to limit the definition of _farmstead_ to just the farm's building, while there could be a lot of additional fenced-in grazing land, which would be the _paddock_.