A corn harvester includes a first stalk roll having a plurality of first blades circumferentially spaced apart by a first angle. A second stalk roll has a plurality of second blades circumferentially spaced apart by a second angle. The first and second stalk rolls are rotatable about parallel first and second axes that are separated by a centerline therebetween. In an operational state when a tip of one first blade is aligned with the centerline, a tip of one second blade is angularly offset from the centerline by a third angle. The third angle is less than 45% of the second angle. The one first blade forms a cross section perpendicular to the first axis having an altitude extending from the tip toward the first axis along a first blade altitude. The cross section of the one first blade is asymmetric about the first blade altitude.