I have found my two Corries booklets. The earlier The Corries has words only,the later (I presume ) The Corries Song Book has words and tunes.
The Hills of Ardmorn by Roy Williamson is in The Corries.
Verses are:
Oh that I could hear the birds again
In the fields of Ardmorn.,
Where the sun lies o'er Scullumvoe,
And the mist silent all around.

Oh that I could see the bracken red,
In the hills of Ardmorn,
And the moss-green inbetween,
And the rain falling softly down.

Oh that I could scent the breeze again,
In thew fields newly turned,
And the storm clouds high above,
And the gulls circling all around.

I assume my booklets were bought at concerts in the late '60s /early '70s, after The Corries Folk Three and Paddy Bell had broken up? I saw them on a number of occasions, in Edinburgh, Galashiels (I think), Dunoon, possibly Glasgow... wish I had a diary of my life instead of vague memories!
If I can find my book of Roy Williamson's life perhaps there will be a mention there - but in fact - it does not really matter whether these are real places or imagined names! These are the words he wrote - which is an improvement on quite a number of songs I has learned from a single hearing or from a crackly record or cassette. Sometimes you just have to take an educated guess....
(I learned a Gordeanna McCulloch song from a Clutha album, could not make out one phrase - years later when our paths crossed I asked her what the phrase was - and she could not remember!!! So I just had to make my own sense of it. As a traditional song it had probably undergone a number of changes with oral transmission!)
Scullumvoe sounds Orcadian to me? But - who knows, who cares?
I believe Ronnie Browne's son maintains The Corries website, so perhaps he can shed light. However - I have never let an inaudible word or misheard phrase stop me from singing a song - just try to make sense of it meantime, perhaps someday you will meet a person who actually kn ows? - If you do not sing the song it may end up being lost forever, which would be sad.