A dominant plant species and insects independently and interactively shape plant community structure and ecosystem function above- and below-ground

It is well-established that dominant plant species and insects independently shape community structure and ecosystem function in terrestrial plant communities. Critically, few studies have assessed the combined effects of these two drivers of plant community structure and ecosystem function above- and below-ground or tracked whether their effects change over time. We factorially manipulated the dominant plant species Solidago canadensis (Canada goldenrod) and insects in an old field at Matthaei Botanical Garden in Ann Arbor, Michigan for three years and quantified their effects on plant diversity, biomass, functional traits, microclimate, and decomposition. Solidago canadensis and insects independently and interactivley shaped plant biomass, the community weighted mean of plant functional traits, soil microclimate, and the estimated decomposition rate of soil organic matter. Overtime, S. canadensis and insects independently and interactively affected the temporal stability of ..., , # A dominant plant species and insects independently and interactively shape plant community structure and ecosystem function above- and below-ground

Dataset DOI: [10.5061/dryad.18931zd8x](10.5061/dryad.18931zd8x)

## Description of the data and file structure

We conducted a full factorial experiment where we manipulated the presence of the dominant plant species *Solidago canadensis* (Canada goldenrod) and insect herbivores in an old-field ecosystem in Michigan. In May 2021, we established 24 5 × 5 meter plots that were at least one meter apart. In August 2021, within each 5 × 5 meter plot, we manipulated *S. canadensis* presence in two 1 × 1 meter subplots at two levels: (1) *S. canadensis* removal and (2) undisturbed control. In *S. canadensis* removal subplots, we removed *S. canadensis* stems by clipping all stems at the soil level. In undisturbed control subplots, we did not remove any plant biomass. We additionally established one 1 × 1-meter random biomass removal subplot with...,