It is typical of the usual tractor-drawn plow that it is connected or supported at its laterally spaced front portions by vertically shiftable hitch means on a tractor and on vertically shiftable linkage means on a furrow wheel. U.S. Pat. No. 3,236,313 discloses an arrangement in which the furrow wheel linkage includes a two-way hydraulic motor and the linkage is mechanically connected to the hitch means so that operation of the motor activates the furrow wheel linkage and hitch means substantially in unison so that substantial leveling of the plow frame is achieved during movement between raised and lowered positions. It is also typical of such plow that, during lowering of the frame from fully raised or transport position to a position for opening up the field, the frame will descend to a greater distance in relation to the front furrow wheel than when it is lowered from transport to the normal plowing position, because, in the opening-up plowing position, the furrow wheel is traveling on unplowed land and, in normal position, the furrow wheel runs in a previously formed furrow. In the recent past it has been necessary to control a hydraulic cylinder in two phases, one stroke for lowering to open-up plowing position and a different stroke for lowering to normal plowing position.