1. In a harrow drawbar assembly which includes a main drawbar frame component, hydraulic means to partially rotate said component, a plurality of drawbar arms secured to and extending rearwardly from said component and a plurality of drag harrow sections supported by said arms; means to apply varying downward pressure upon said sections to control the ground engaging characteristics thereof, said means including a vertically situated rod, means mounting said rod for substantially vertical sliding movement in the distal end of the arms, the lower end of said rod being linked to said harrow section between the front and rear ends thereof, and a cable and spring assembly extending between the upper end of said rod and an anchor point adjacent the inner end of said arm, said cable and spring assembly including a sheave adjacent said distal end of said arm around which said cable engages, said cable and spring assembly including a tension spring, said tension spring being anchored by one end thereof to adjacent the inner end of said arm, said cable being anchored by one end thereof to the other end of said spring, said cable, after extending around said sheave, running substantially parallel to said rod and being secured to the upper end of said rod by the other end of said cable.

3. A harrow drawbar assembly comprising in combination a plurality of drawbar arms extending rearwardly from said drawbar and being secured thereto for partial rotation thereby, drag harrow sections operatively connected to the distal ends of said arms, said operative connection including rods slidable vertically through each of said arms at the distal ends thereof, said rods being link connected by the lower ends thereof to said draw harrow sections and means to apply varying downward pressure upon said sections to control the ground-engaging characteristics thereof, said means including means mounting said rods for said substantially vertical sliding movement in the distal ends of said arms, ad a cable and spring assembly extending between the upper end of said rods and anchor points adjacent the inner ends of said arms, said cable and spring assembly including a sheave adjacent said distal end of said arm around which said cable engages, said cable and spring assembly including a tension spring, said tension spring being anchored by one end thereof to adjacent the inner end of said arm, said cable being anchored by one end thereof to the other end of said spring, said cable, after extending around said sheave, running substantially parallel to said rod and being secured to the upper end of said rod by the other end of said cable.