Abstract: Disclosed are a method and apparatus (10) for cataloging or dividing a given field, under irrigation by an irrigation system (100), into a plurality of zones which can be monitored for irrigation water and chemical requirements and then, delivering by way of the irrigation system, the appropriate amount of irrigation water and/or chemicals to each zone as so defined. Each of the sprinkler assemblies (105) is independently controlled by a solenoid operated valve (16), responsive to a control module (15). The control modules (15), in turn, are electronically interconnected with a data acquisition and control unit (12) which is capable of sending to the control modules (15) coded signals for either activating the sprinkler head (105) or deactivating each individual sprinkler head (105).