Site description and location selection
This experiment was performed at the West Virginia University (WVU) Animal Sciences farm in Morgantown, West Virginia (39°40’10.2”N, 79°55’53.6”W). This site is located next to the former Baker’s Ridge Mine Site (National Mine Repository 304559) and is managed as a cool-season grass pasture (detailed site description available in Kane et al. 2023, in review ). Miscanthus plots were established in 2019 using a fully randomized block design with 4 fertilization treatments replicated 8 times for a total of 32 plots (Kane et al. 2023,in review ). Each plot is 5 m2 and was established by planting 25 miscanthus rhizomes using 1 m2 grid spacing (site map, SI Fig. 3a ). Plots are fertilized yearly with treatments that include no fertilization, low-level inorganic N additions (28.5 kgN/ha), high-level inorganic N additions (57 kgN/ha), and organic fertilization (local manure, ~57 kgN/ha). Due to logistical constraints for sample size, we utilized the control, high-level inorganic, and organic fertilization treatments for this experiment.