Abstract: A pop-up riser in a vegetation sprinkler in which the riser is forced out of a housing by water pressure. The riser has a nozzle at its upper end. The riser is normally held in a retracted position by a coil spring. A serrated ring is fixed either on the housing or riser and resilient tabs extending respectively from the other are engaged with the serrations. Precise spray direction is achieved by relative rotation between the tabs and serrations. The nozzle configuration has an outwardly directed flow passage having a portion of its wall cutaway and has its upper end terminating in a conical wall to achieve an optimum spray pattern . A seal is fitted in the housing so as to surround the riser and so as to engage the riser as it is moved upwardly to extended sprinkling positions.