Abstract: A climbing stick for climbing upward e.g., to a hunting tree stand, can be locked in a closed position to deter unauthorized persons from climbing on it. A vertical center pole has a plurality of foot pegs are hinged to it at predetermined locations thereon, disposed on the right and left sides of the pole. The foot pegs swing up to a vertical closed position and swing down to a horizontal open position. Left and right vertical side rails are connected by hinges or pivot pins to the ends of the foot pegs on the respective left and right sides. Mating lock fixtures on the left and right vertical side rails allow the left and right vertical side rails be locked when they are closed against one another, and prevent unauthorized access. An extruded aluminum tree hook or jaw assists in mounting the climbing stick against a tree.