An irrigation system includes a series of spaced mobile towers； support structure connecting the mobile towers to each other； a water-carrying conduit supported by the mobile towers and the support structure； and a plurality of water emitters connected to the conduit for delivering water to a ground surface. At least one of the mobile towers includes an integrated motor and wheel assembly for driving the mobile tower. The integrated motor and wheel assembly includes a wheel； a tire, track or other ground-engaging component mounted on the wheel； and a direct drive motor positioned in or adjacent the wheel for directly driving the wheel. The direct drive motor drives the wheel without a drive shaft and right-angle gear boxes.
