Experimental setup: There will be four treatments: removal of all plant species except S. canadensis, S. canadensis removal, random plant biomass removal, and control. Experimental plots will be one m2, with 8 replicates of each removal treatment making 32 treatment plots total. The random biomass removal treatment will determine if removal effects are due to an overall decrease in plant biomass or if the identity of the species removed matters. I will remove plants in late May and maintain removals throughout the growing season. I plan to establish this manipulation at Greenstar Meadow (but I will work with UMBS staff to find the best possible location for the project). Plant community monitoring: Every two weeks after removal treatments are established, I will visually estimate the percent cover of each plant functional group and measure plant functional traits including plant height, SLA, leaf area, and leaf dry matter content to calculate functional diversity (Siefert and Ritchie 2016). I will measure functional traits of 5 randomly selected individuals of each species for each plot (Siefert and Ritchie 2016). I predict that the percent cover of non-Solidago plant species will be greater in S. canadensis removal plots than in control plots (McCain et al. 2010, Souza et al. 2011). In plots where all plant species except S. canadensis are removed, I predict that because S. canadensis will be released from competition, S. canadensis cover and productivity will be higher relative to control plots. Arthropod community monitoring: After establishing removal treatments, I will place pitfall traps in each plot for 72 hours and perform a 30 second bug-vac sweep to directly collect arthropods from plants every two weeks. Pitfall traps will be 50mL (30 x 114 mm) plastic centrifuge tubes partially filled with a mixture of water and unscented dish soap, making them small enough so as not to trap vertebrates. I will calculate arthropod abundance, species richness, and trophic structure (Welti et al. 2020). I will additionally estimate herbivory of S. canadensis leaves by collecting 3 fully expanded leaves from a randomly selected S. canadensis stem in each plot and quantifying the amount of leaf area damaged by herbivores (Coltharp et al. 2021). I predict that arthropods across trophic levels will increase in abundance as plant biomass accumulates. In S. canadensis removal plots, I predict that the abundance of Solidago specialist herbivores will decline while generalist herbivores will be less affected (Messina 1978). Changes in herbivore abundance in response to removal treatments may alter the trophic structure of arthropod communities, with herbivore loss leading to a higher abundance of predators relative to herbivores (Welti et al. 2020). Monitoring ecosystem processes and abiotic environment: I will bury nylon tea bags and measure normalized vegetation difference index bi-weekly to examine the effect of plant removals on decomposition and productivity (Hutchinson and Henry 2010). I will remove tea bag nutrient supplements after the experiment. I will evaluate removal treatment effects on light availability, soil moisture, soil temperature, soil pH, and soil nitrogen content by analyzing soil samples collected every two weeks (Fukami et al. 2006) References Coltharp, E., Knowd, C., Abelli-Amen, E., Abounayan, A., Alcaraz, S., Auer, R., ... & Weber, M. (2021). Leaf hair tufts function as domatia for mites in quercus agrifolia (fagaceae). Madroño, 67(4), 165-169. Fukami, T., Wardle, D. A., Bellingham, P. J., Mulder, C. P., Towns, D. R., Yeates, G. W., ... & Williamson, W. M. (2006). Above‐and below‐ground impacts of introduced predators in seabird‐dominated island ecosystems. Ecology letters, 9(12), 1299-1307. Hutchison, J. S., & Henry, H. A. (2010). Additive effects of warming and increased nitrogen deposition in a temperate old field: plant productivity and the importance of winter. Ecosystems, 13(5), 661-672. McCain, K. N., Baer, S. G., Blair, J. M., & Wilson, G. W. (2010). Dominant grasses suppress local diversity in restored tallgrass prairie. Restoration Ecology, 18, 40-49. Messina, F. J. (1978). Mirid fauna associated with old-field goldenrods (Solidago: Compositae) in Ithaca, NY. Journal of the New York Entomological Society, 137-143. Siefert, A., & Ritchie, M. E. (2016). Intraspecific trait variation drives functional responses of old-field plant communities to nutrient enrichment. Oecologia, 181(1), 245-255. Souza, L., Weltzin, J. F., & Sanders, N. J. (2011). Differential effects of two dominant plant species on community structure and invasibility in an old-field ecosystem. Journal of Plant Ecology, 4(3), 123-131. Welti, E. A., Kuczynski, L., Marske, K. A., Sanders, N. J., de Beurs, K. M., & Kaspari, M. (2020). Salty, mild, and low plant biomass grasslands increase top‐heaviness of invertebrate trophic pyramids. Global Ecology and Biogeography, 29(9), 1474-1485