NOTE for reproducibility of our resultsFor all our analyses, we removed three plots from the original design (in all cases both split-split plots containing new/old communities)B1A12, quadrat with Org soilThis 8-species mixture had to be excluded because of missing data and the data not accurately representing the plant community.B2A05Festuca pratense monoculture had to be exlucded because the wrong species was planted.B2A15Onobrychis viciifolia monoculture had to be excluded because it was such an extreme outlier and the data did not accurately represent the community.