There is a version on YouTube and assuming it's the right tune as I haven't heard it before it goes something like
Intro
D5 (played xx0235) and under that is a little tune on the
4th and 3rd strings that goes
D F# A A G F# G A | D F# A A G F# D
Verse 1
D5 C D5
Across the hills black clouds are sweeping
C G/B D5
Carry poison far and wide
D C D
And the grass has blackened underfoot
D C D
And the rose has withered and died
Verse 2
D5 (plus similar to intro playing underneath)
But the rose is still as red now and the grass is still as green
C
And it must have been a shadow in the distance you have seen
D C D5
Yes it must have been a shadow you have seen
And that's about it