FIELD: agricultural engineering. SUBSTANCE: apparatus has frame, brackets, poles, and rotavator drum with undercutting knives. Rotavator drive has cylindrical reducer, intermediate shaft, cone reducer and telescopic cardan shaft with general- purpose pivot joints at its ends. Apparatus is further provided with driveless drum-type cutter which is mounted so as to be repositioned and moved in vertical plane along frame in front of rotavator drum. Knives of driveless-type cutter are removably mounted on its carcass and are provided with single-sided inverted blades. Double-sided knives of rotavator drum are provided with cutting edges formed on their side surfaces in symmetry with geometrical axis of locating slot on mounting part. Curved working part of each knife has in its concave portion single-sided symmetrical cutting edges. Apparatus is used for preliminary preparing of natural licorice undergrowth massif for commercial extraction of licorice roots. EFFECT: reduced power consumed for cutting black head part of licorice, enhanced reliability in operation and increased efficiency. 2 cl, 7 dwg
