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The impact and intensity of defoliation and site water status on regrowth and above ground production of herbaceous riparian species was assessed in 3 small C channel streams in June and July of 2000-2003 in Harney County, Oregon (3937 to 4593 feet elevation). Four blocks or sites of 5 x 10 m each were selected in each channel stream. In each block, 40 x 50 cm paired clipped (treated) and unclipped (control) plots were set within 1 m (“close macroplot”) and 4 m (“far macroplot”) distant from the edge of the stream. Each plot pair was randomly assigned to a clipping date (either June or July) and stubble height (2, 4 and 6 in) combination. At the end of the growing season all plots, including the controls, were clipped to 1 cm to calculate regrowth and annual aboveground production. Weight and average height were compared between clipped and unclipped plots to estimate regrowth. In addition, water table depth to 50 cm was measured weekly. Graminoid species composition was measured in 2003.