Abstract: A hydraulic actuator that can be used on trip plows to hold the trip blade in its operative downward position and to control the return of the trip blade after tripping. The actuator has a body with first and second ends. A piston rod reciprocates within the tube. A plate with a channel is positioned within the tube a spaced distance from the tube ends. The plate creates an oil reservoir between the plate and the piston rod. A reciprocating piston is positioned within the tube between the second end and the plate. A spring is mounted between the second end and the reciprocating piston and normally biases the reciprocating piston into engagement with the channel normally closing the channel. The piston rod moves in the direction of the plate when the trip blade hits an obstruction, forcing the oil through the channel moving the reciprocating piston and opening the channel allowing oil to flow into an oil chamber created between the reciprocating piston and the plate.