Utah State University Extension
Billbugs are weevils, a type of beetle, in the genus Sphenophorus. At least 10 billbug species are known pests of turfgrass and can be found in both warm and cool season turfgrasses throughout the United States. Though billbug adults do feed on the leaves of turfgrasses, it is the larvae that cause visible damage. Larvae feed within the stems and on roots of grasses, leading to the development of yellow or brown patches, with the potential to escalate into large patches of dead turfgrass. Billbug management in turfgrass presents a number of unique challenges, but early monitoring and informed integration of multiple strategies can help mitigate these challenges, and proper turfgrass management can help conceal mild to moderate levels of billbug damage.
Wickwar, Desiree and Ramirez, Ricardo, "Billbugs in Turfgrass (Sphenophorus spp.)" (2022). All Current Publications. Paper 861.