In 1988, wildfire burned over 50% of the Jones Creek watershed near Yellowstone Park, Wyoming. Crow Creek, an adjacent watershed, was unburned. Water quality data collected from 1989-1993 may show the fire's effect on weathering and nutrient transport. Jones Creek had 25-75% larger concentration of dissolved solids than Crow Creek during the sampling period. Both streams revealed molar ratios consistent with the stoichiometry of andesine and pyroxene hydrolysis in the trachyandesites that underlie the basins. During 1989, nitrate transported from the unburned Crow Creek basin peaked at 2 mmol ha-1 s-1. This was twice as much as Jones Creek, possibly indicating a source from ash fallout. By 1992 these rates diminished to 0.1 mmol ha-1 s-1 in Crow Creek and increased to 1.8 mmol ha-1 s-1 in Jones Creek, suggesting later nitrate mobilization in the burned watershed. Phosphorus transported from Jones Creek basin averaged 0.011 mmol ha-1 s-1 during summer 1989, but fell to 0.004 mg ha-1 s-1 in subsequent years.In 1988, wildfire burned over 50% of the Jones Creek watershed near Yellowstone Park, Wyoming. Crow Creek, an adjacent watershed, was unburned. Water quality data collected from 1989-1993 may show the fire's effect on weathering and nutrient transport. Jones Creek had 25-75% larger concentrations of dissolved solids than Crow Creek during the sampling period. Both streams revealed molar ratios consistent with the stoichiometry of andesine and pyroxene hydrolysis in the trachyandesites that underlie the basins. During 1989, nitrate transported from the unburned Crow Creek basin peaked at 2 mmol ha-1 s-1. This was twice as much as Jones Creek, possibly indicating a source from ash fallout. By 1992 these rates diminished to 0.1 mmol ha-1 s-1 in Crow Creek and increased to 1.8 mmol ha-1 s-1 in Jones Creek, suggesting later nitrate mobilization in the burned watershed. Phosphorus transported from Jones Creek basin averaged 0.011 mmol ha-1 s-1 during summer 1989, but fell to 0.004 mg ha-1 s-1 in subsequent years.