WASHINGTON — Russell Hedrick, a North Carolina farmer, flies drones to spray fertilizers on his corn, soybean and wheat fields at a fraction of what it would cost him to use a conventional ground spreader. As a volunteer rescuer, Hedrick uses thermal drones to search for people trapped by mudslides and cargo drones to send water and baby formula to those who are stranded — something he did after Hurricane Helene . Now he is fretting that one day he will have to ground his drone fleet. Most