Abstract: A one-piece flexible guard for excluding dirt and other foreign matter from the internal parts of a pop-up sprinkler. More particularly, a flexible circularly shaped piece of material which can be attached to the edge of the fixed housing assembly of a pop-up sprinkler. Said material having a circular hole in its center in which the pop-up sprinkler protrudes, said movable part being securely attached to said material along the edge of said circular hole. The guard being attached to the sprinkler in such a way so as to exclude foreign matter from the internal parts of the sprinkler while permitting the movable nozzle portion free vertical or horizontal movement. In an up position the outer perimeter of the guard forms a dam. The sprinkler also may provide fluid to wash the dirt from outside of the dam portion of the guard when the nozzle is in the extended or up position.