Recorded native plant richness rose in 119 bison-grazed Konza plots from 2008–2010 to 2016–2018; extra list change over an earlier eight-year span was uncertain

We tested whether recorded native plant lists in fixed Konza Prairie plots changed more across the 2011–2012 drought than over an earlier span of the same duration. We used open PVC02 version 25 data and the 2025 species workbook. A taxon entered a three-year list when it occurred in at least two years. We kept 119 upland plots in six bison watersheds with records in both growing-season parts in all selected years. From 2008–2010 to 2016–2018, equal-watershed mean richness rose from 32.74 to 37.10 taxa per plot. Mean losses were 7.05 and gains were 11.41; mean retention was 78.6%. Mean Sørensen dissimilarity was 0.265, against 0.249 for 2000–2002 to 2008–2010. The paired excess was 0.0165, with a reference 95% Student t interval of −0.0399 to 0.0728 across six watershed differences. This is not evidence of equivalence. Planned list rules also gave intervals across zero for excess dissimilarity. An added audit found an abrupt Oxalis label switch and a change in collection personnel ID. Hypothetically pooling the two Oxalis codes changed the excess to −0.0044; grouping native records by current genus gave −0.0143. Neither grouping is a confirmed correction of species identity. The same bison population uses all six watersheds. The results describe recorded lists and cannot separate drought, ordinary change, fire and recording effects. We preserve source files, provenance, code, list and coverage tables, figures and an offline repeat with independent list checks.

Konza Prairie · plant composition · species richness · drought · bison · temporal beta diversity · taxon resolution · reproducibility