I put the tune as you indicated into my bagpipe music writer and played it, then searched for 'The Apple Tree' hymn. I found 'Jesus the Apple Tree', written by Elizabeth Poston, which sounds similar - there was a boys choir in one video singing a similar tune. Some of the notes are a little different in duration from what you indicated ('hold' and 'long hold' aren't very helpful - I'd prefer to see the notes and rests, or at least indicate quarter, eighth, sixteenth, etc.).