ABSTRACT The effect of activated charcoal as an amendment to water agar medium on teliospore germination was analyzed for two species of wheat-infecting bunts, Tilletia controversa and T. tritici, and two related wild-grass infecting species, T. bromi and T. fusca. Final percentages of teliospore germination, area under the germination progress curves (AUGPC), and a standardized AUGPC (SAUGPC) on carbon agar and water agar were compared among strains. Carbon agar (CA) significantly increased the final germination percentage of teliospores, AUGPC, and SAUGPC when compared with water agar (WA) for all taxa under study. Additionally, CA reduced significantly the incubation (i.e., lag) period when compared with WA for teliospores of T. bromi, T. controversa, and T. fusca. Bovine serum albumin and polyvinyl pyrrolidone were used as alternative chemical adsorbent amendments to WA to establish the role of activated charcoal in the medium. Only media amended with bovine serum albumin and activated charcoal improved the final germination percentage of all taxa. Polyvinyl pyrrolidone was not significantly better than water agar.