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Fire is the dominant disturbance in big sagebrush ecosystems. Of the three subspecies of big sagebrush (Artemisia tridentata), mountain big sagebrush (ssp. vaseyana; MBS) is the most resilient to disturbance, but still requires favorable climactic conditions and a viable post-fire seedbank for rapid recovery. We used data from 13 central Utah burn sites and a space-for-time substitution strategy to identify trends in seed production during post-fire recovery. We hypothesized that seed rain (mean seeds produced/ m2) would be maximized before stands reached equilibrium due to higher individual plant fecundity and relatively low levels of intraspecific competition. Using estimates of population density and individual plant fecundity, we estimated potential seed rain for three size classes of MBS and used forward stepwise regression analysis to identify significant factors influencing seed production over time. Density for small (basal stem diameter (BSD) < 1 cm) and medium-sized (BSD = 1-3 cm) plants was consistently low and was not affected by time since fire, while large plant (BSD > 3 cm) density steadily increased (p=0.0062), suggesting continual recruitment over time. Fecundity for all size classes was significantly correlated with previous winter or spring precipitation (p range =0.0006-0.0154). Large plant fecundity dominated reproductive output and decreased as total plant density increased (p=0.0133). Seed rain increased with total MBS cover (p=0.0028) suggesting that losses in individual plant fecundity were more than compensated by higher densities of seed-producing plants. Total MBS cover and seed rain appeared to level off between 20 and 30 years after fire even though stand structural characteristics may not have fully stabilized. Results partially support our hypothesis that the time required to reach MBS seed rain maximum was not tightly bound to indicators of stand maturation. Understanding the factors that influence post-fire seed production can help land managers better manage for successful recovery.