Albert Barnes Commentary Jeremiah 50:16

"Cut off the sower from Babylon, and him that handleth the sickle in the time of harvest: for fear of the oppressing sword they shall turn every one to his people, and they shall flee every one to his own land." — Jeremiah 50:16 (ASV)

The population is to be destroyed so utterly that the rich fields of Babylonia are to remain untilled.

They shall turn - The full force of the words will be seen if it is remembered that it had been the policy of Nebuchadnezzar to compel citizens selected from the vanquished nations to settle in Babylonia.