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The effects of wildfire ash on soil properties, particularly its role in soil sealing, have far-reaching consequences for hydrological processes. The western United States faces an increasing frequency and intensity of wildfires, which has implications for post-fire soil behavior. Here, we aim to advance the understanding of soil sealing and hydrological fluxes following wildfires, focusing on the impacts of ash on the ground surface after the first rainstorms following a wildfire. Using controlled laboratory experiments, we assessed changes in hydraulic conductivity at the soil-ash interface, utilizing the mini-disk infiltrometer, KSAT, and HYPROP instruments. Soils treated with ash demonstrated an increase in water retention and unsaturated hydraulic conductivity but a decrease in field-saturated hydraulic conductivity. At the soil interface there was an increase in hydraulic conductivity. The (Kfs) for the experiment flumes rose from 48.5 cm/day to 112.97 cm/day post-burn (p-value = 0.00015) and declined from 112.97 cm/day to 51.58 cm/day post-rainfall (p-value = 0.000015). The impact of slope angle on ash erosion was minimal. Â鶹ÊÓƵ 80% of the ash applied to the surfaces is retained after rainfall across different slope areas. Ash affects soil hydraulic properties in the short term, but its impacts can vary depending on environmental factors such as rainfall intensity and suction conditions.