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In grassland-dominated systems, belowground bud banks determine plant population dynamics.  Responses to disturbances are largely driven by the bud bank's ability to generate future aboveground growth originating from belowground axillary buds.  This study examined bud bank dynamics for C4 rhizomatous/caespitose grass Bouteloua gracilis, C3 rhizomatous grass Pascopyrum smithii, and C3 caespitose grass Hesperostipa comata, following fire in mixed-grass prairie.  Belowground axillary buds were counted and classified 8-24 hrs prior to burning and within 8-24 hours after burning to assess immediate direct effects of summer, fall, and spring prescribed fire on patterns of bud bank activity, dormancy, and mortality.  Season of fire treatments were randomly assigned to 20 × 20 m plots and were replicated four times.  Thermocouples were used to assess three fire intensity variables at the plot level:  maximum temperature, heat duration, and heat dosage.  Summer fires had increased fire intensity measurements compared to spring and fall prescribed burns.  Fire did not result in immediate direct mortality of B. gracilis, P. smithii, or H. comata buds (P ? 0.15).  Spring fire increased B. gracilis bud activity by 71% (P < 0.01), resulting in an 80% decrease in dormant buds (P < 0.01).  In contrast, summer fire reduced B. gracilis active buds by 36% (P < 0.01) and increased dormant buds by 73% (P < 0.01).  Fall fire stimulated 38% of P. smithii buds to become active (P < 0.01).  Fire did not influence any immediate bud dynamics for H. comata (P ? 0.28).  Season of fire directly influenced bud activity for these species throughout growing and dormant seasons following fire.  Using season of fire to manipulate bud bank dynamics could enhance post-fire management strategies based on the trajectory of bud development and bud dynamics following fire.