This section is from the book "Ancient Legends, Mystic Charms, And Superstitions Of Ireland", by Jane Francesca Wilde. Also available from Amazon: Ancient Legends, Mystic Charms, And Superstitions Of Ireland.
There were two brothers who had a small farm and dairy between them, and they were honest and industrious, and worked hard to get along, though they had barely enough, after all their labour, just to keep body and soul together.
One day while churning, the handle of the dash broke, and nothing being near to mend it, one of the brothers cut off a branch from an elder-tree that grew close to the house, and tied it to the dash for a handle. Then the churning went on, but, to their surprise, the butter gathered so thick that all the crocks in the house were soon full, and still there was more left. The same thing went on every churning day, so the brothers became rich, for they could fill the market with their butter, and still had more than enough for every buyer.
At last, being honest and true men, they began to fear that there was witchcraft in it, and that they were wronging their neighbours by abstracting their butter, and bringing it to their own churn in some strange way. So they both went off together to a great fairy doctor, and told him the whole story, and asked his advice.
" Foolish men," he said to them, " why did you come to me ? for now you have broken the spell, and you will never have your crocks filled with butter any more. Your good fortune has passed away, for know the truth now. You were not wronging your neighbours ; all was fair and just that you did, but this-is how it happened. Long ago, the fairies passing through your land had a dispute and fought a battle, and having no arms, they flung lumps of butter at each other, which got lodged in the branches of the elder-tree in great quantities, for it was just after May Eve, when butter is plenty. This is the butter you have had, for the elder-tree has a sacred power which preserved it until now, and it came down to you through the branch you cut for a handle to the dash. But the spell is broken now that you have uttered the mystery, and you will have no more butter from the elder-tree."
Then the brothers went away sorrowful, and never after did the butter come beyond the usual quantity. However, they had already made so much money that they were content. And they stocked their farm, and all things prospered with them, for they had dealt uprightly in the matter, and the blessing of the Lord was on them.