A recently burned area near Wallsburg, Wasatch County, Utah, was sampled to determine if differences existed between the soil algal flora of a burned area and that of an adjacent ecologically similar unburned area. Soil samples were cultured and analyzed to determine presence and relative frequency of living algae. The frequency of visible algal patches present after eight days of culturing was much higher in the unburned soil samples than in the burned samples. Percent relative frequencies and absolute densities of diatoms were also determined. Diatom floras of the two areas were very similar. However, the absolute densities of diatoms were significantly greater in the unburned samples. The major effect of the burn was to decrease algal biomass, although the flora remained remarkably similar. © Society for Range Management. Abstract reproduced by permission.