A disk blade has an outer perimeter, a first side wall, a second side wall, and a central hub. A plurality of fingers extend laterally at an angle θ from said first side wall. The fingers preferably comprise metal round bars curved to form part of an elliptical geometry inserted at a perpendicular angle to a vertical angle of said disk blade. The bars are arranged at locations equidistant around said disk blade and are disposed at a depth x from said outer perimeter of said disk blade. Preferably, the depth x is at least ≥；one (1) inch.
