1. In a rock picker having a conveyor for elevating rocks from the ground, and a rotatable tumbler for removal of foreign material from the rocks, the improvement comprising a frame mounting said conveyor and tumbler and extending rearwardly therefrom, a storage box mounted to the rear portions of said frame to the rear of said tumbler, a second conveyor assembly fixed to the forward end of said storage box and substantially centered in transverse direction on said box and having an inlet end positioned closely adjacent the rear of said tumbler in a first box position, means to pivotally mount a rear portion of said box to the rear portion of said frame, and hydraulic cylinder means to pivot said box and said conveyor from position adjacent said tumbler to a dumping position.

6. In a rock picker having a frame with front and rear portions and means for lifting rocks from the ground and moving them rearwardly on the frame, the improvement comprising a storage box mounted to the rear portions of said frame to receive rocks from said means for lifting rocks in a first box position, a conveyor assembly associated with the forward end of said storage box, means to pivotally mount a rear portion of said box to the rear portions of said frame, first hydraulic cylinder means to pivot said box from the first box position to a dumping position, and means to support said frame for movement along the ground comprising a wheel assembly including torque arm means pivotally mounted to said frame, wheel means at the opposite ends of said torque arm means, and second hydraulic cylinder means connected to said torque arm means adjacent said wheel means and connected to said frame substantially directly above the connection thereof to said torque arm means and operable to directly lift said frame relative said wheel means as the torque arm means pivots about its pivotal mounting to said frame.