A bale loading trailer has a bale supporting frame mounted on wheels. A fork assembly is pivotally mounted beside a front end of the frame configured to engage a bale when in a lowered position, and to disengage the bale when in a raised position such that the bale moves onto the front end of the bale supporting frame. A hydraulic cylinder moves the fork assembly between positions. A hydraulic motor driven conveyor chain assembly extends along the bale supporting frame, and loaded bales rest on, and move along the frame in concert with, the conveyor chain. A valve circuit connects the hydraulic cylinder and the hydraulic motor drive such that as the fork assembly moves from the raised position to the lowered position, hydraulic fluid flows from the hydraulic cylinder through the hydraulic motor drive and causes the conveyor chain assembly to move a bale length rearward.
