warmXtrophic plant-soil interaction greenhouse experiment, Kellogg Biological Station, Hickory Corners, MI, 2021

Climate warming influences plant communities through both direct effects, such as changes in temperature, and indirect pathways mediated by changes in soil microbial communities. These microbe-mediated indirect effects may alter plant traits and ecosystem dynamics in ways that are often overlooked in studies focused solely on the direct impacts of warming. To test these microbe-mediated indirect effects, we used field-conditioned soil from a 7-year (2015-2021) warming experiment (warmXtrophic) in an early successional plant community in Hickory Corners, Michigan, USA at Michigan State University's Kellogg Biological Station Long-Term Ecological Research site. In a greenhouse during 2021, we assessed how warmed versus ambient soil inocula influenced plant growth and traits of two species: Trifolium pratense (red clover) and Phleum pratense (Timothy grass). We measured above, below, and total biomass, height, number of leaves, timing of germination, leaf % carbon and nitrogen, C:N ratio, specific leaf area (SLA), and greenness (a proxy for chlorophyll content). We also measured the timing of emergence of the cotyledon and first leaf for Trifolium pratense.