Restored marginal farmland benefits arthropod diversity at multiple scales

The loss of resource‐rich non‐crop habitat is a hypothesized driver of arthropod decline on farms, implying recovery with restoration. Alternatively, chronic arthropod loss may limit colonization to abundant taxa, especially crop pests. Here, we test the impact of restoring marginal farmland on agriculturally important arthropods on 13 conventional farms across a 10,000 km2 region of central North America with approximately 92% crop cover. We examined local richness by habitat (crops, restored prairie, remnant forest), spatial turnover among habitat and farms, and regional comparisons between farm and non‐farms using iNaturalist data. Sampling approximately 13,000 individuals identified to family or lower, restored prairie had twice the abundance of arthropods compared to crop and forest, with 44% of all families detected, 66% of beneficial families, and 94 unique taxa despite their recent construction (