The Dingus Natural Area is a 69.4 ha, forest-dominated tract located in extreme east-central Kansas. It is passively managed for scientific research. A floristic inventory of the site revealed 351 species of vascular plants, 91% of which were native. The five largest families (Asteraceae, Poaceae, Fabaceae, Cyperaceae, and Rosaceae) contained 45% of the species. Hemicryptophytes made up 41% of the species, and 12% of the species were conservative or highly conservative based on coefficients of conservatism. Populations of 13 state-rare species were documented at the site, including one species known in Kansas only from Dingus Natural Area. Six primary vegetation types occurred on the site: oak-hickory forest, mesic forest, glades, sparse vegetation communities, seep communities, and ruderal. Forests accounted for 57% of species occurrences at the site. Glades, while limited in area compared to forests, accounted for 26% of species occurrences.