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In North American prairie it is acknowledged that defoliation events via bison grazing consistently followed fire. Given this evolutionary fire-grazing interaction, our objective was to determine whether post-fire timing of defoliation altered subsequent productivity and species composition. Following the April 2013 Pautre wildfire in the Grand River National Grasslands of South Dakota, we installed exclosures in three locations along the border of the fire. Grazing exclosures were paired across the fire line to create a "burned" and "unburned" exclosure at each of the three locations. Four plots were demarcated in each exclosure. Three plots were defoliated via mowing either 2, 4 or 6 months following the fire with the fourth maintained as a control. Productivity and species composition data were collected in November 2013, June 2014, August 2014 and July 2015. Fire increased productivity 56% during the 2013 growing season following the fire (P=0.0330). During the 2014 growing season, there was a trend for burned sites to maintain greater production (P=0.0832). June defoliation resulted in the greatest current-year productivity regardless of fire treatment, while all other treatments resulted in similar productivity (P=0.0299). Fire increased the presence of Hesperostipa comata, Melilotus officinalis, Carex filifolia (21 v 6%, 15 v 1%, 22 v 10%; P=0.0494, 0.0265 and 0.0479 respectively) during the first growing season. June defoliation reduced Agropyron cristatum (P=0.0228) and increased M. officinalis (P=0.0133) as compared to controls, but remained similar to other mowing treatments. Koeleria macrantha increased via August defoliation (P=0.0015) whereas Nassela viridula decreased from either June or August defoliation (P=0.0133). Initial results suggest that fire effects on productivity is limited to the first growing season following fire whereas defoliation effects manifest the second growing season following fire. Additionally, both fire and timing of defoliation will disparately affect community composition.