A harvesting unit with a combine, having a user cab. A harvesting apparatus, advanced by the combine, has a frame and a harvesting assembly on the frame configured to process severed crop over a width between spaced sides of the frame. A fluid delivery system discharges pressurized fluid in discrete streams each directed to at least one of: a) facilitate severance of crop by the harvesting assembly; and b) facilitate advancement of severed crop rearwardly in relationship to the frame for further processing. A user can selectively vary at least one of: a) a volume of pressurized fluid; and b) a direction of pressurized fluid in the discrete streams. A control system has at least one actuator accessible and operable from outside of the cab through a user input to cause the at least one of the volume of pressurized fluid discharged, and direction of the pressurized fluid, in the discrete streams to be varied.