A blade assembly for cutting roots is installed on a hand-carried weed cutter or hand-carried side walk edger. The blade assembly has a central blade support that supports a central blade. A plurality of cutting blades are stacked on both sides of the central blade to form a stack of blades. The stack of blades is secured together by fasteners that pass through openings in the blades. The central blade and each of the plurality of cutting blades has a plurality of teeth. Outermost blades in the stack of blades are smaller in diameter than the blades directly adjacent to the outermost blades.