Seeding is a key management tool for arid rangeland. In these systems, however, seeded species often fail to establish. A recent study in Wyoming big sagebrush steppe suggested that over 90% of seeded native grass individuals die before seedlings emerged. This current study examines the timing and rate of seed germination, seedling emergence, and seedling death related to this demographic bottleneck. We seeded monocultures of two native perennial bunchgrasses, Pseudoroegenaria spicata (Pursh)Á. Löve and Elymus elymoides (Raf.) Swezey, and one introduced bunchgrass, Agropyron desertorum (Fisch. ex Link) Schult., in 2007, 2008, and 2009 and tracked sown seed and seedling fate. Across the study years and species we found that germination was rapid and high, with species obtaining 50% germination by December, less than 2 mo after planting. Emergence of germinated seed did not occur until late February for A. desertorum and March for the two native grasses. In 2007 the majority of emergence and death was constrained to several weeks, whereas in 2008 and 2009 emergence and death was distributed across several months. The timing of seedling emergence did not influence survival probability or midday plant water potential (probability of exceedance , 0.05). Survival probabilities once seedlings emerged were greater for native species (0.71) than A. desertorum (0.51) in 2 of the 3 study yr (probability of exceedance. 0.98). The early germination of grasses following fall seeding, and the long 2-to 3-mo period that germinated grass seed remain in the soil before emerging, support the hypothesis that seedling recruitment might be limited largely by ecological processes and conditions during winter or early spring (such as soil freeze-thaw events, seed pathogens, or physical crusts). Delaying seeding to early winter or spring and other management tools that mitigate these factors driving this bottleneck might greatly improve restoration outcomes in these systems. Resumen Las resiembras son una herramienta clave de manejo para pastizales á ridos. En estos sistemas, sin embargo, las especies sembradas a menudo no se establecen. En un estudio reciente en un pastizal de Artemisia en Wyoming se sugiere que má s del 90% de los individuos sembrados de pastos nativos mueren antes que la plántula germine. Este estudio examina laépoca y tasa de germinación de las semillas, la aparición de la plá ntula, y la muerte de plá ntula relacionadas con el cuello de botella demográ fico. Se sembraron monocultivos de dos especies nativas de pastos amacollados, Pseudoroegenaria spicata (Pursh)Á. Löve y Elymus elymoides (Raf.) Swezey, y también un pasto amacollado introducido, Agropyron desertorum (Fisch. ex Link) Schult., durante 2007, 2008, y 2009 y se le dio seguimiento a las semillas sembradas así como el destino de las plántulas. A través de los años de estudio y especies se vio que la germinación fue rá pida y alta, con la obtención de la germinación del 50% en diciembre, menos de 2 meses después de la siembra de especies. La aparición de sem...