I think looking at maps does help us. I had started to compile all this before I saw John's reply above, but it has taken me a while to get all the snippets together.
I am attaching snips of OS maps of varying dates as one image and all carefully dated. All have north at the top, so the angle is consistent. Contours are roughly north-west to south east orientation with higher ground on the right-hand side of each map. It is not possible to say which is the ‘front’ of the house.
In 1871 we can see a house of a very asymmetric shape. To the south east there is an area of woodland – deciduous trees according to the map. To the north of the house, also deciduous trees.
In 1898 there are some coniferous trees now marked. The house seems to have changed its shape a little, but is roughly the same foot-print.
In 1910, we see major differences. The house is now rectangular in shape and the area that was previously shown as all wooded to the south-east is now showing an embankment on three sides, enclosing an area of lower ground. (One could speculate that this is for a croquet lawn or tennis court. ) The trees are all marked as deciduous. NB NO POND
In 1968, the house has been extended on the north-eastern side (a narrow extension) and to the north-west (an extension that is the full width of the house). The embankment can be clearly seen (sorry, cut off a bit) and the rill like water feature appears for the first time under the word ‘Vron’ and extends beyond it. Also note that there are no coniferous trees around the house.
The map revisions published in 1938 and 1953, together with the 2.5 inch map of 1956 do not show the water-feature or other significant changes.
So, if we accept that the photo was taken before the house at Vron Yw was rebuilt in 1906 or so, then the following must apply:
there would not be a pond/water-feature
some 17th century architectural features might be visible as indicated by other published sources.
If the photo was taken after 1906, the photo must have been taken somtime between 1956 or so and 1967/8 – from map evidence. Indications are that the photo is not of this date.
Nell