Evaluation of pitfall traps for capturing arthropods in turfgrass

Abstract The turfgrass system is a complex ecosystem where many soil‐born arthropods dwell and co‐exist. Often, turfgrass is threatened by many pests, such as billbugs ( Sphenophorus spp.; Coleoptera: Curculionidae). Monitoring pests is an important strategy for effective management decisions. The four‐way linear pitfall trap is commonly used to determine adult Sphenophorus spp. population in turfgrass; however, it is challenging to deploy, labor‐intensive, and requires regular intensive maintenance. The objectives of this study were to (1) compare trap captures of Sphenophorus spp. and predators using solo‐cup, pail, two and four‐way linear pitfall traps, and (2) evaluate whether increasing the number of simpler traps improves capture efficiency of soil‐dwelling arthropods. The captures of adult Sphenophorus spp. and carabids in the four‐way linear pitfall trap were not consistently greater than those caught in the two‐way linear or single solo‐cup pitfall traps. The four and eight solo‐cup pitfall traps captured more Sphenophorus spp. and most soil‐active predators than the four‐way linear pitfall trap. The pail pitfall trap was not efficient in capturing soil‐active arthropods. Thus, increased numbers of solo‐cup pitfall traps, at least four in a defined trapping area, could be an alternative to the four‐way linear pitfall trap to sample or monitor Sphenophorus spp. or carabids. Deploying and maintaining a solo cup is much easier than a four‐way linear pitfall trap.