Nine burned Cedar Creek plots gave no clear one-year Bray–Curtis turnover contrast after fertilizer stopped, 2015–2022

We tested plant change after fertilizer stopped in Cedar Creek field B. Earlier work on these same plots found richness gains and partial composition recovery. We measured Bray–Curtis distance on relative live herbaceous biomass between moving sample strips in consecutive years. The primary set had nine annual-fire plots at three high past nutrient rates and three one-year intervals in 2015–2022. Mean distance was 0.293 on stopped halves and 0.189 on continued halves. The paired difference was +0.104, with a 95% whole-plot bootstrap interval of −0.008 to +0.195. A paired t interval also included zero. Thus, the primary result did not establish the direction of the contrast or equal turnover. A planned check of two two-year gaps gave +0.154 (+0.090 to +0.223). The direct two-year minus one-year contrast remained uncertain. One plot strongly affected the primary estimate and was retained. Secondary metrics and data checks changed interval decisions. The result is limited by nine plots, three one-year gaps, moving strips, sampling dates and no independent field B half-assignment ledger. We provide unchanged open inputs, provenance, all code, 32 repeatable outputs, figures and an independent raw-data calculation.

grassland · nutrient cessation · plant composition · temporal turnover · Cedar Creek · Bray-Curtis · paired plots · reproducible analysis