The purpose of this study was to track year-to-year variation in arthropod communities of the host plant Ligusticum porteri (Apiaceae). In each study year (2017-2020), we used sweep nets to sample the arthropods at each of twenty sites containing populations of L. porteri. Sampling took place the end of June (June 28-30th), and we standardized sampling effort across years. Two field technicians netted insects from vegetation at a consistent pace for 30 seconds each. We sorted and identified insects to Order using a dissection microscope and a project-specific taxonomic key. Non-insect arthropods were also counted but not identified to additional taxonomic levels.