Secretary Tom Vilsack has left the Agriculture Department just one week before the end of his tenure, leaving Donald Trump scrambling to find his replacement. Vilsack, who has led the USDA for the past eight years, told employees in an email that Friday will be his final day. He has said he wants to remain involved with agriculture after leaving government, but has not detailed those plans. As Vilsack leaves the department, many in rural America worry that agriculture may be a low priority for the new administration. It is the only Cabinet position Trump has not moved to fill, though rural voters were key to delivering him the presidency.