A tandem spindle drum row unit arrangement includes a rotary knife offset ahead of the forward drum to sever plants. A feeder rotor with fingers projecting through grid bar structure gently directs plants laterally into a standing row prior to substantial engagement by the spindles on the forward drum. Feeder column rotational speed is synchronized with ground speed. The knife, having a common axis with the rotor, operates at a higher speed for an efficient cut. The feeder column includes curved fingers which project through vertically spaced bars on a guard assembly to positively separate the plant from the fingers. The feeder column and rotary knife are driven through separate slip clutches. A kicker wheel between the drums moves plant material rearwardly.