Here are the lyrics (as best as I can understand them) in the version sung by The Black Family. Slightly different than those posted by Mad Maudlin.

THE PLOUGHBOY LADS

Well, I was na but sweet sixteen
With beauty's chance a bloomin' - O
It's little, little did I think
At nineteen I'd be greitin' - O

CHO: Well the ploughboy lads, they're all braw lads
    But they're false and they're deceivin' - O
    They'll take your all and they'll gang awa'
    And leave the lassies greitin' - O

Well, I was fond of company
And I gave the ploughboys freedom - O
To kiss and clap me in the dark
When all my friends were sleepin' - O

CHO:

Well, if I did know what I know now
And I took me mother's biddin' - O
I wouldn't be sittin' by our fireside
Cryin' "Hush a ba, my baby" - O

CHO:

Well, it's hush a ba, for I'm your ma
But the Lord knows who's your daddy - O
And I'll take care and I'll beware
Of the ploughboys in the gloamin' - O

The lyrics indicate to me that it's of Scottish origin. (The use of awa', braw, etc.) According to Child's English and Scottish Popular Ballads, greit (pronounced greet) means to weep or cry (I've heard it sung in this song as "grieve" as the pronunciation is similar and the sentiment expressed is pretty much the same) and clap means "pat, fondle, embrace". Gloaming is also Scottish, I think. It seems as though every group that has performed this song adapts the lyrics to their own taste or understanding.

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