Turfgrass cover influences the abundance of beneficial arthropods in sod farms

Turfgrass hosts multitudes of herbivores and some of them are pests such as the hunting billbug, Sphenophorus venatus vestitus Chittenden (Coleoptera: Curculionidae), which reduces the quality of turfgrass during nipping. With turfgrass being a crop of economic and ecological importance, management of pests attacking this crop should encourage the conservation of other beneficial invertebrates in the ecosystem. Thus, our objective was to quantify and compare the abundance of beneficial arthropod groups across turfgrass stands at three cover levels (0 %, ∼50 %, and 100 % cover) representing early, intermediate, and fully established sod. We hypothesized that beneficial arthropods would be less abundant in early-stage (sparse cover) sod than in fully covered turf, due to reduced habitat and resources at early stages. In 2021 and 2022, zoysiagrass ( Zoysia spp.) sod fields with 0 %, 50 %, and 100 % turfgrass cover were selected, and arthropod abundance was documented using pitfall traps. The numbers of carabids, staphylinids, and parasitic hymenopterans in 2021 and the parasitic hymenopterans in 2022 were less abundant in turfgrass at the early stages of development. However, dermapterans were more abundant in the turfgrass at the early stages of development than fully covered. The abundance of Araneae increased when the turfgrass fully covered the ground. Although beneficial arthropods were prevalent at all stages of turfgrass development, they were less abundant at the early stages. The implications of the results for the development of ecologically driven management strategies for pests, such as S. venatus vestitus , conserving beneficial arthropods in sod farms are discussed. • Turfgrass hosts diverse arthropods in all stages of grass cover in sod farms. • Beneficial arthropods tended to be lower when turfgrass cover was <100 %. • Spiders and parasitic hymenopterans were more abundant in increased grass cover. • Occurrence of dermapterans was higher in low grass cover. • Early pest interventions may be less disruptive to beneficial arthropods.