A power-driven lawnmower having a main chassis supporting an operator, a pair of forward drive wheels, and a steering wheel utilizes a floating mower deck which covers or houses at least one driven mower blade. The deck is connected to the main chassis by a pair of arms terminating in ball joints affixed to the mower deck which is supported on ground engaging wheels such that the mower deck follows the contour of the ground. A flexible drive belt is connected to a constant power take off element on the main chassis and to the drive mechanism on the deck such that belt is entrained over a constant distance due to the connection of the arms to the chassis and the mower deck. A zero turning radius rear steering mechanism is operatively connected to the steering wheel and to a mechanism for disengaging one of a pair of forward drive wheels from motive power from the engine during a turn, thereby enabling the maneuverability of the machine, and a foot operated reversing mechanism is provided which can readily be engaged to reverse the direction of travel of a power-driven lawnmower. For safety concerns the mower is equipped with a gravity actuated brake which stops movement of the mower and the blade when the gas pedal is released. When the gas pedal is pressed again the vehicle moves forward again with the mower running again. Vehicle remains stopped if foot pedal is pressed into neutral position. Mower runs full rpm's when gas pedal is depressed allowing shuttle action in trimming forward or rearward by command of clutch pedal operated by left foot. Mower is disengaged by a hand-operated lever on left side.