A transfer station for collecting and transferring harvested material to large transport vehicles includes a hopper, in which harvested material accumulates, supported on a rigid frame. The hopper may be elevated from a lower "collection" height to an upper "transfer" height that facilitates release of harvested material into the transport vehicle. In one embodiment, the contents of the hopper are poured into a collection vehicle by tilting the entire transfer-station frame. In a second embodiment of the invention, the transfer-station frame does not tilt. Instead, the hopper is equipped with a sloped floor member. When lifted vertically and positioned over a collection vehicle, the hopper discharges by gravity as soon as an opening is established at the base of the slope.