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Perennial bunchgrasses are critical to maintaining sagebrush plant communities but seeding of native bunchgrasses following fire has met with only limited success. Previous research indicates that blacked soils beneath burned sagebrush canopies have increased seeding success for perennial bunchgrasses when compared to interspace locations. We investigated soil moisture and temperature across white, brown, and black soils and tested the relationship between soil color and seedling demographics for seeded bluebunch wheatgrass. We used a randomized block design with three treatments and five replications conducted in a Wyoming big sagebrush community in southeast Oregon. The study site was roto-tilled prior to establishing 50 x 50 cm plots in each of two years. We installed soil temperature/moisture probes at two cm depth in each plot. Plots were seeded in November of each year with 250 viable bluebunch wheatgrass seeds. Plots were then covered in a < 1mm layer of white, brown, or black aquarium sand and sand was re-applied as needed over time. We counted emergent seedlings weekly from snowmelt through May of the year following planting. Soil moisture during the emergence period (March - May) was highest for white soils and lowest for black soils (p < 0.05); soil temperature was highest for black soils and lowest for white soils (p < 0.05). Year one was characterized by a warm and dry emergence period and year two was relatively cool and moist. Emergent seedling density was highest (p < 0.05) for white soils; surviving seedling density (on June 1) was highest (p < 0.05) for white soils in year one and black soils in year two. Black soils had greater success in a year with lower soil temperatures and adequate soil moisture. When soil moisture is limited, increased soil temperature on black soils led to seedling desiccation and death.