2 Samuel 18:7-11

Where the people of Israel were slain before the servants of David, and there was there a great slaughter that day of twenty thousand men.

For the battle was there scattered over the face of all the country: and the wood devoured more people that day than the sword devoured.

And Absalom met the servants of David. And Absalom rode upon a mule, and the mule went under the thick boughs of a great oak, and his head caught hold of the oak, and he was taken up between the heaven and the earth; and the mule that was under him went away.

And a certain man saw it, and told Joab, and said, Behold, I saw Absalom hanged in an oak.

And Joab said unto the man that told him, And, behold, thou sawest him, and why didst thou not smite him there to the ground? and I would have given thee ten shekels of silver, and a girdle.