The influence of standing dead biomass on available solar radiation, leaf temperature and leaf water potential of Andropogon gerardii in unburned tallgrass prairie was compared to burned prairie in eastern Kansas. The standing dead reduced photosynthetically active radiation incident on emerging shoots by 58.8% in unburned compared to burned prairie during the initial 30 days of the growing season. Aboveground production in unburned prairie was similarly reduced during this period (55.4%) compared to burned prairie. Leaf temperatures in A. gerardii were greater in unburned prairie than in burned early in the season, but were nearly equal by the end of the growing season. The maximum elevation of leaf temperature in unburned prairie above burned was 9.5 C. The maximum unburned leaf temperature measured was 41.5 C compared to 39.4 C in burned prairie. Lower windspeed adjacent to leaves in unburned prairie resulting in reduced convective cooling may have caused higher leaf temperature in unburned prairie. Leaf water potential was significantly lower in unburned prairie than in burned prairie early in the season but was higher in unburned prairie by late season. The seasonal minimum leaf water potential in burned prairie was -1.60 MPa compared to -1.45 MPa in unburned prairie. The combined effect of these post-burn differences in solar radiation, leaf temperature and leaf water potential may be significant in contributing to the lower production in unburned compared to burned tallgrass prairie